==2000==
8 March 2000 Memphis TN, 4 killed (shot) (http://murderpedia.org/male.W/w/williams-frederick.htm)
25 March 2000 Martinsville IN, 7 killed (vehicular homicide) (http://murderpedia.org/female.K/k/kirby-judy.htm)
6 April 2000 Oakland County MI, 5 killed (arson) (http://murderpedia.org/male.D/d/deering-juwan.htm)
20 April 2000 PA Reading PA, 4 killed (vehicular homicide - train) (http://murderpedia.org/male.D/d/diazsantiagoca.htm)
28 April 2000 Pittsburgh PA, 5 killed (shot) (http://murderpedia.org/male.B/b/baumhammers.htm)
4 September 2000 Ava OH, 6 killed (multiple) (https://en.wikipedia.org/wiki/List_of_rampage_killers_(familicides_in_the_United_States))
18 October 2000, Ankoa County MN, 5 killed (multiple) (http://murderpedia.org/male.D/d/dame-lawrence.htm)
21 October 2000 Tampa FL 5 killed (multiple) (http://murderpedia.org/male.L/l/levingston-dexter.htm)
21 November 2000 Farmington Hills MI 5* killed (shot) (http://murderpedia.org/male.M/m/moukalled-jihad.htm)
23 December 2000 Colville WA 4 killed (shot) (http://murderpedia.org/male.L/l/lembcke-william.htm)
26 December 2000, Wakefield MA, 7 killed (shot) (https://en.wikipedia.org/wiki/Wakefield_massacre)
==2001==
10 January 2001 Jacksonville FL 4 killed (shot) (http://murderpedia.org/male.H/h/hurley-billy.htm)
23 January 2001 Lufkin TX, 5 killed (shot) (http://murderpedia.org/male.F/f/franco-lucio.htm)
5 February 2001 DuPage County IL, 5 killed (shot) (http://murderpedia.org/male.B/b/baker-william.htm)
23 February 2001 Santa Barbara CA, 4 killed (vehicular homicide) (http://murderpedia.org/male.A/a/attias-david.htm)
8 March 2001 Greer SC, 4 killed (shooting) (http://murderpedia.org/male.H/h/hilderbrand-michael.htm)
4 April 2001 Brooklyn NY 4 killed (reckless driving/DWI) (https://en.wikipedia.org/wiki/Joseph_Gray_(police_officer))
11 April 2001 Chula Vista CA 4* killed (shot) (http://murderpedia.org/male.M/m/molter-eugene.htm)
25 April 2001 Tate County MS, 4 killed (shot) (http://murderpedia.org/male.B/b1/brawner-jan-michael.htm)
15 May 2001 Lodi CA, 4 killed (shot)( http://murderpedia.org/male.J/j/johnson-roger-leroy.htm)
20 June 2001 Houston TX, 5 killed (drowned) (http://murderpedia.org/female.Y/y/yates-andrea.htm)
30 August 2001 Sioux City IA 7 killed (multiple) (http://murderpedia.org/male.M/m/moss-adam.htm)
7 September 2001 Simi Valley CA, 4 killed (shot) (http://murderpedia.org/male.H/h/herrera-rodriguez.htm)
8 September 2001 Sacramento CA, 5 killed (shot) (http://murderpedia.org/male.F/f/ferguson-joseph.htm)
22 September 2001, Fairfield Al, 6 killed (arson) (http://www.al.com/news/birmingham/index.ssf/2016/08/alabama_mass_murders_56_killed.html)
16 December 2001 Lincoln County OR 4 killed (multiple) (http://murderpedia.org/male.L/l/longo-christian.htm)
==2002==
19 February 2002 Los Angeles CA, 5 killed (arson) (http://murderpedia.org/male.G/g/garcia-adair-javier.htm)
23 February 2002 Yamhill County OR 6* killed (shot) (http://murderpedia.org/male.B/b/bryant-robert.htm)
25 March 2002 Merced CA, 5 killed (shot) (http://murderpedia.org/male.H/h/hogan-john.htm)
4 August 2002 Dallas County TX 5 killed (shot) (http://murderpedia.org/male.O/o/ochoa-abel-revilla.htm)
26 August 2002, Crenshaw County AL, 6 killed (multiple) (http://www.al.com/news/birmingham/index.ssf/2016/08/alabama_mass_murders_56_killed.html)
16 October 2002 Baltimore MD, 7 killed (arson) (http://murderpedia.org/male.B/b/brooks-darrell.htm)
24 October 2002 Tucson AZ, 4 killed (shot) (http://murderpedia.org/male.F/f/flores-robert-stewart.htm)
21 December 2002 Detroit MI, 5 killed (shot (http://murderpedia.org/male.W/w/wolfenbarger-john.htm)
21 December 2002 Tillamook State Forest OR 4 killed (multiple) (http://murderpedia.org/male.M/m/morris-edward-paul.htm
==2003==
5 January 2003 Hidalgo County TX, 6 killed (shot) (http://murderpedia.org/male.G/g/garza-humberto.htm)
18 May 2003 Harris County TX 4 killed (shot) (http://murderpedia.org/female.P/p/paolilla-christine.htm)
6 July 2003 Bakersfield CA, 5 killed (stabbed) (http://murderpedia.org/male.B/b/brothers-vincent.htm)
8 July 2003, Meridian MS, 7 killed (shot) (https://en.wikipedia.org/wiki/Lockheed_Martin_shooting)
18 July 2003 Harris County TX, 4 killed (shot) (http://murderpedia.org/female.P/p/paolilla-christine.htm)
15 September 2003 Colorado Springs CO 4* killed (shot) (http://murderpedia.org/male.R/r/raghunandan-rutendra.htm)
18 November 2003 Philadelphia PA 5 killed (arson) (http://6abc.com/news/arrest-made-in-2003-arson-that-killed-5-family-members/1309853/)
27 November 2003 Gary IN, 5 killed (shot) (http://murderpedia.org/male.D/d/dennie-terry-lee.htm)
==2004==
12 March 2004 Fresno CA, 9 killed (shot) (http://murderpedia.org/male.W/w/wesson-marcus.htm)
3 July 2004 Kansas City KS 6* killed (shot) (http://www.nbcnews.com/id/5353964/ns/us_news-crime_and_courts/t/six-dead-kansas-workplace-shooting/)
21 November 2004, Meteor WI, 6 killed (shot) (https://en.wikipedia.org/wiki/Chai_Vang)
8 December 2004 Columbus OH, 4 killed (shot) (http://murderpedia.org/male.G/g/gale-nathan.htm)
==2005==
26 January 2005 Glendale CA, 11 killed (caused a train wreck) (http://murderpedia.org/male.A/a/alvarez-juan-manuel.htm)
12 March 2005, Brookfield WI, 7 killed (shot) (https://en.wikipedia.org/wiki/Terry_Ratzmann)
11-12 March 2005 Atlanta GA 4 killed (shot) (http://murderpedia.org/male.N/n/nichols-brian-gene.htm)
21 March 2005, Red Lake MN, 10 killed (shot) (https://en.wikipedia.org/wiki/Red_Lake_shootings)
25 March 2006 Seattle WA, 7 killed (shot) (https://en.wikipedia.org/wiki/List_of_rampage_killers_(Americas))
28 September 2005 DuPage County IL, 4 killed (beaten) (http://murderpedia.org/male.H/h/hanson-eric.htm)
29 August 2005 Sash TX 5* killed (shot) (https://www.chron.com/news/houston-texas/article/Gunman-kills-himself-after-deadly-rampage-1916640.php)
13 December 2005 Boston MA, 4 killed (shot) (http://murderpedia.org/male.C/c/carnes-calvin.htm)
there doesn't seem to be anything here