In some cases you can get a spot approval by the lender. However there are other things you need to be concerned with as well. The occupancy % of the complex. If it is under 50% owner occupancy or if the association is over 15% delinquent in their dues the lender is likely to reject the complex for financing.
Nicholas hit my response. Many "townhome" style properties are legally condos and subject to the same rules and FHA approvals as a traditional condo would be. If you think about it a "townhome" is not a property type in the lending world. It is a condo, or attached PUD.
Townhomes is a term that is thrown around but it's just a term that sounds better than the original term, "rowhouse". Anyways, it is used to describe both attached condos or pud's (planned unit developments). If the townhouse you are interest ed in is legally a pud, you should be okay. If it is legally a condo, you should probably try to choose one off the search engine above.