How about asking ebay sellers who use links to, or information from, the Lansing Heritage Library in their auctions to make a $1-$2 donation per link?
Seems like most anytime I search for Altec or JBL there's usually some auctions with links to the library (9 auctions today).
Could just send email to the buyer & seller after the auction asking them to make a small donation if the site was helpful in the transaction.
I wonder how many folks first found the site through ebay auctions, trying to find info on items they were buying or selling?