You could consider a UK Fiance visa, but I suspect you will run into the same problems of requiring applicants to obtain a visa before traveling to the UK. She may need to leave the country & apply. Then you could apply for a Marriage visa.

The UK Border Agency's info on "Can you get married or register a civil partnership in the UK?" is probably your best resource.

Anyone have experience in this area?

 

My situation is a bit similar.
I married my british girlfriend in nigeria and i currently have a uk visit visa which allows me to visit.
Sinc it takes so long to process the residency permit in nigeria and she cannot stay in nigeria that long because she is working, so can I process my resident permit in Uk whilst on that visit visa even though we are already legally married in nigeria?

Please, help with valuable information!