A fantastic checklist site with THOUSANDS of checklists can be found at Jeff Allender's House of Checklists.

The card collectors site Beckett.com has many checklists.

This terrific Sportscaster card site has front and back images of all Sportscaster cards.

Non-T&F checklists - these checklists are for series which don't include any track and field cards, but for which I couldn't find complete (or nearly complete) checklists anywhere else.