ISP don't make deals with spammers. At least ones that don't want to become their own private network don't. I work for an ISP in the abuse dept. I have to deal with this on a daily basis. One recent spammer we caught signed up 15 seperate accounts all with stolen cards. At 11:30 on a Friday night he started spamming, After over 400 complaints an hour from AOL the accounts were caught and all nuked within 3 hours of his start time. If we had ignored this AOL would have blocked our mail servers and we'd have had a LOT of upset users that were unable to send email to grandma at AOL the following Saturday.
If you have an idea of a service you wish to use I'd suggest going to Google "groups" and searching for their domain and or the software and watch for posts about them in the "news.admin.net-abuse.email" newgroup. Better yet just pop in there and ask about them. This is the ISP abuse dept hangout. If they have a bad rap they will tell you in a second.