I love all sports. I particularly love the "alternative" leagues of the 1970's and early '80's. These are some of the sites dedicated to that category of leagues.
http://remembertheaba.com/ This a great website. I've visited this site every couple of months for years. I never get tired of going to it.
http://abamemorabilia.com/ -A lot of pictures
http://www.sover.net/~spectrum/nasl/naslhist.html A lot of individual
player data.
http://www.tampabayrowdies.com Lots of great Rowdies photos.
http://thememphisrogues.blogspot.com/ Blog dedicated to the Memphis Rogues
http://mytampabayrowdies.blogspot.com/ Very nice Rowdies blog, great photos
http://washingtondiplomats.blogspot.com/ Blog dedicated to the
Diplomats
http://naslmemories.blogspot.com/ Lots of NASL photos
http://www.timbersfanpage.com/ Lots of Timbers photos.
http://www.ftlauderdalestrikers.com/ Nice site dedicated to the Strikers.
http://www.soundercentral.com/MuseumLobby.htm Nice NASL Sounders and MISL Stars photos.
http://davebrett.com/-Dave has an amazing collection of NASL DVDs. He will trade or sell you copies. All his stuff is first rate.
http://homepages.sover.net/~spectrum/ Nice data on all American soccer leagues.
http://www.funwhileitlasted.net/: Lots of NASL programs and information.
http://www.oldfootballshirts.com/en/index.php This site is
primarily European jerseys. They have some NASL jerseys and are
adding content all the time.
http://www.soccershirts.org/ Very nice collection of international jerseys. Has some NASL and MISL jerseys
http://www.thehistoryofwomensfootball.com/ This is a site dedicated to women's soccer. It is very well done.
www.thenationalfootballshirtcollection.com
has a number of NASL jerseys along with a very nice collection of
international jerseys.
http://www.soundercentral.com/MuseumLobby.htm Nice NASL Sounders and MISL Stars photos.
http://www.funwhileitlasted.net/: Lots of MISL programs and information.
http://wichitawingshistory.com/ Wichita Wings site
http://www.oursportscentral.com/misl/ General MISL data
http://mislvideo.com Nice list of games to trade
http://www.charlottehornetswfl.com/ Lots of Charlotte Hornets pictures
http://www.wfl1974.com/index.html Everything you need to know about the Birmingham Americans and Vulcans.
http://www.worldfootballleague.org/ World Football League statistics.
http://www.mlbstyleguides.com/ This is also a commercial site. I think most jersey collectors are sports fans first. Most of us collect or will collect multiple sports. I bought their guide to baseball jerseys. It is well worth the money.