It is the simplest way to determine an immigration lawyer in houston. Some of them might charge you less than $5,000 for a consultation and some of them could charge you more than $5,000. But it all depends on you what type of service that you are looking for.
I am sure that most people who look into hiring an immigration lawyer will be getting information from the internet because they find this option more convenient as opposed to searching lawyers individually through phone book or visiting their offices face-to-face (although I believe there are still many good lawyers out there). If online search has not helped then try contacting one or two potential candidates directly but make sure no lawyer charges upfront fees before providing services (just like any other kind of attorney) otherwise your case may end up costing much more than expected.