I decided to re buy it as I lost my disk years ago. I was charged for the purchase, but i got a "your bank as declined this transaction" message. I checked with my bank and the charge posted...three times. Is there a number to call for customer support. I haven't found one, thats why im asking.

http://www.gog.com/support/contact
Here is how you contact support

Show them the proof from the bank and try and get them to fix the issue.

It's possible that both sides (GOG and your bank) are correct. What you may be seeing is a hold on your account for a set of potential transactions that were never completed at GOG's end, due to online connection issues.

Ask your bank whether they are transactions or holds, and (if they're holds) when they expire. If the bank still insists that they're full transactions, then go with SheBear's advice.