Originally posted by John Meyers:
Cant they use the internic service ?
Sending your customers to other web sites (internic uses Verisign to query .com and .net TLD's) is not a good business model.
Perhaps you could exec an nslookup on the requested domain. If it comes back with a negative result, the domain should be available.
There can be issues since there is a delay of several hours between a domain being registered and that registration being propogated through the DNS. I'm not sure how to handle that.