I used pairNetworks with Americart for this in the past:
elmbrook.org/women/summit/reg_cc.html
but now the client needs the results for a different conference with a lot of people attending in comma delimited format for importing into Excel. I used Americart's Express Form which can't store the results in comma delimited format (the regular "shopping cart " does). Does anybody have any other solutions? The client is doing their own credit card processing, I just need the secure server for storing the credit card info. I can do enough programming to put the results in Excel format but not enough to do secure transactions. Thanks.