I examine my on-line bank statement(s) every couple of days. For my US accounts, I use Mint.com as an aggregator, to fetch transactions and put them in a single .csv file.

I know people purposely use throw-away reloadable debit cards (Wal*Mart, WesternUnion) for use with sites that don't pass the sniff test. Put enough on the card to buy a trial for a month, then add more funds if nothing shady was going on.