Any experiences out there? I'm happy to pay a travel agent (within reason) to take most of the strain.
This is general information on the travel agency that is 'close to the Tajik embassy'.
If you turn up to the embassy prior to 9am you can place your name on the waiting list. As an example, I turned up at 8am and 12 people had already put their name down. I'm not sure it's even worth putting your name down in light of the next bit of information.
The travel agent is in an unmarked white metal door on the right hand side a few metres down the alley next to the 'Caravan' restaurant, which is next to the Tajik embassy. The lady there will apply for your visa on your behalf for USD $35 plus the cost of the visa itself (example: $50 for an Australian passport holder, visa only). This is loosely called 'visa support' (not the same as an LOI). If you choose to use her services, ensure you bring one passport photo. I engaged her services at about 9:30am, and was told to return 5pm the same day to pick up the visa - which I did; all went well.
Alternately, I suppose you could just put your name down in the book held by the embassy guards, wait for your turn, then make the application yourself in the embassy.
I chose to use the services of the agency because I'd frankly had enough of the guards taking me aside and trying to 'help' me (telling me to come back later, telling me to call him when I do, blah blah blah). The reason I found out about exactly where the travel agent is located is because, eventually, one such guard led me there. Sure, of the $35 he probably gets a cut, but if you'd rather not wait around all day to apply for the visa yourself, ignore the guards and go straight to the travel agent.
Marc

Thanks for the advice, Marc. I'm hoping to get the Taj visa in London but who knows? If it has to be in Tashkent I'd rather pay a bit of money and get it painlessly!
Information on getting the GBAO permit in Tashkent
Originally I was planning to get the permit when in Dushanbe, as I had read the Tajik embassy in Tashkent would not issue it.
Not true. Yesterday I used her services again to get the permit. Called her to confirm (+99890 931 96 35, she speaks some English), dropped off my passport at 9:30am, paid her USD $40, and picked up my passport at 5pm with the two stamps (i.e. the permit) therein: one square one with a hand written permit end date corresponding to the end date of your Tajik visa, and a round one on top of that.
Reason for doing all this: read some info that applying online to an agency, or trying to get the permit in Dushanbe, was either too much hassle or took too long. Perhaps true, perhaps not, but having it hassle free in one day is pretty darn good!
I'm not affiliated with this agency in any way. I don't even know its name :)