Just to clarify that you should have a connection to Ireland but the rules are now a lot looser than the past. [broken link removed]
But as the OP wants a .COM, you only need to Google "Register Domain" to get a whole list of places you can register also for quite little cost. You don't need a
solicitor, you only need to have a unique name that has not been already registered.
When you get to the point of running a business and trading then you may need advice on whether to be self employed, a company, tax implications etc. There are loads of free resources and advice to help you though this phase also.