Who do I contact about a 1983 LA Lakers team autographed basketball?

I would like to find out what the worth is of a autographed 1983 LA Lakers team basketball. The names on the ball are: Kareem Abdul Jabbar, Larry Shipp, Bob McAdoo, Jamual Wilkes, Mike McGee, Magic Johnson, Byran Scott, Kirk Rambis, Calvin Gauiett, Aaron Nater, Michael Kephell, James Worthy and Michael Cooper. I used to go to a lot of games when I was younger and was in the inside croud. Was lucky and got their basketball signed at a after party. I had it in storage and is in mint condition. What steps do I take to find out what its worth. I checked out e-bay and also googled it and no answer. Thank you for your information.