how do you buy an ico before it is on an exchange? do you need a special wallet for it as well?
No need for special wallet. Some ICOs are easy to buy us dollar. Some ICO are need MyEtherWallet or coinbase wallet. Most of the ICO are accepting US dollar, Everything should be your ICO company terms and conditions. It is easy to buy in anywhere. But your tokens are received in automatically. If any issues are happens in tokens it is server problem. So It will be automatically credited your wallet.