I just found a few thousand baseball cards That I had when I was younger almost all of them are perfect they range from 1987 to about 1994. Topps,fleer,upperdeck,score,a complete 1990 set 1 and 2 of leaf etc. Is there anything that I can look for in all of those cards or is there anyone that buys them in bulk?

the 1990 leaf set is desirable. the rest aren't going to get you much.
Though there are a few random cards in each year that are worth a few bucks here and there. The key is your 90 leaf set. The Griffey, Frank Thomas, Sammy Sosa are all desirable from that set.

The others, if in very nice condition, can be desirable as well.

Yea and on beckett.com there is usually a place to sell you collection

Thanks YEAH the 1990 Leaf set I and II is PERFECT thanks for help

Most sets from the late 80s early 90s are worth nothing except for key rookies.

sadly everything for the early 80's to the mid to late 90's was so over produced that the values are very little. But remember the good old time when you could buy a pack of cards for $.50. So many of them existed, that now ebay sellers and dealers are selling them with warehouses left to be opened.