Basically just post up what you can get. A good site to find out is here:
http://www.samknows.com/broadband/checker2.php
My availability (currently with Telewest Blueyonder):
Congratulations, you are in a broadband enabled area.
The following services are available in your location:

BT Wholesale ADSL

BT Wholesale ADSL Max

Telewest Cable
BT ADSL broadband availability
You are connected to the
Devonport telephone exchange.
ADSL is available in your area

Your exchange is also enabled for ADSL Max services
According to BT Wholesale, your line should be able to support a
5.5Mbps or greater ADSL connection via ADSL Max.
BT SDSL broadband availability
You are connected to the
Devonport telephone exchange.
SDSL is not yet available in your area
According to BT Wholesale, your line can support an SDSL service of 2Mbps (Amber).
LLU xDSL presence at your exchange
You are connected to the
Devonport telephone exchange.
The following table details the availability of LLU services at your location.
Be Unlimited is not yet available in your area
Bulldog is not yet available in your area
Carphone Warehouse will be available in your area, but the precise date is unknown
Easynet is not yet available in your area
Edge is not yet available in your area
Homechoice is not yet available in your area
Node4 is not yet available in your area
Pipex is not yet available in your area
Tiscali is not yet available in your area
Wanadoo is not yet available in your area
Zen is not yet available in your area
Cable broadband availability
The following information details the availability of cable broadband in your area.
Telewest Blueyonder is available in your area
Wireless broadband services
The following information details the wireless services available to you.
LTT Broadband is not yet available in your area
Now (Formerly Netvigator) is not yet available in your area