No need to use a travel agent at all - arrive at the airport with a 30 day tourist visa and you have the run of the country.

- Hotels are rarely full - just turn up and bargain.
- If it's something of a tourist hotspot (e.g. Dunhuang) there will be local companies available to sort whatever you need sorting.
- If it's a bit off the tourist trail make sure you;ve done your homework and you should easily be able to sort a taxi.

Indeed, in many ways the flexibility you have by not having things pre-arranged is an advantage.

The only caveat is the permit for Tibet - what that situation will be like in 2009 is anyone's guess.