I saw this over at the TripAdvisor forums, does it help?
http://www.tripadvisor.com/ShowTopic-g2939...n-Ashgabat.htmlYou can get a transit visa, if you have a visa for Uzbekistan and if you are coming let's say Iran you can apply for transit visa in Turkmen Embassy in Mashed.
Or you can just travel in Ashgabat city, then you do not need a guide inside of Ashgabat. The guide will meet you in border and assist to get to Ashgabat and in Ashgabat you are alone.
I travelled through Ayan Travel, and it was OK. You can find out about them at
www.ayan-travel.com
Hope it will help.