Yes, it happens to lots of people. You need to find out why you got suspended. They do not do it randomly. Most everyone reporting back as to why has been given a good reason.
Some common reasons players have reported being suspended:
1. Failed transaction - insufficient funds or payment declined by bank
2. Mismatch in Billing, Account, and/or PayPal address and name information
3. Playing from outside the region registered to the account. For example, if you access the RMAH from Asia when you are registered at a US address it bans you.
4. Playing from a different country than the one you are registered too, even if within the same Region
4. Missing billing information such as a zip code
Call them to get it resolved. http://us.battle.net/support/en/article/contact
Some tips for calling:
1. The phone lines are always full these days (They support all of D3, WoW, and Starcraft). Spam dial immediately until you get in queue and then stay there!
2. Cell phones hate being on hold and can disconnect. Use a land line (free in the US) or Skype (free to download and call them with anywhere in the world).
3. Be prepared for a 45 min + wait on hold
4. Be prepared to prove your identity by answering questions or giving Battle.net game keys