Today, folks look back nostalgically at the Negro Leagues, but it was a business and owners took competition very seriously. Only two months after MLB's success, "East" and "West" teams trotted onto the very same Comiskey field for a game of all-black All-Stars. The Western team starter (and Chicago American Giants star) was Willie Foster.
Foster threw a complete-game victory in 1933, beating a trio of East pitchers. The West team played their starters all 9 innings, a rare move for star-driven games of any sort. Both All-Star games became annual traditions, with MLB running theirs in July and the Negro Leagues playing in August or September.
The Negro Leagues struggled financially following WWII and surviving teams returned to barnstorming by the 1950s. Their annual All-Star game lasted until 1962 and teams occasionally played a second game outside Chicago. A semi-integrated MLB also ran two All-Star games from 1959 to 1962, perhaps in an effort to "drown out" interest in the all-black teams. (My conjecture, but plausible given baseball's cutthroat management style.)
Artist Bob Laughlin self-published this 36-card salute to Negro Leaguers and sold them by mail order, like his 1968 World Series (#5 set profile) and 1972 Great Feats sets (#5 set profile). It apparently proved successful enough to warrant a follow-up, 1978's Long Ago Black Stars (#5 set profile).
This set contains a bunch of HOFers, scans available at this Collectors Universe forum post.
Value: Foster cost me $8 in 2006. I estimate singles run at least $5 and definitely more for HOFers.
Fakes / reprints: Haven't seen any reprints in the market.