What kind of place are you looking for Stunt? There's the Aztec Spa where a room is around £120 per night with nice facilities. I've used this chain a lot and like it but not stayed at the Bristol one. Same junction as Cribbs I think from memory.
If you want somewhere really cheap and out of centre, my DH stayed in a v basic B&B not far from Parkway station, I could find out details. Around £50 per room. Probably not the nicest but it did for him and friends on a 2 day hockey tournament.
Otherwise there is a lot of choice in the City centre - I have used the travelodge, hotel ibis, Marriott (both), thistle. Range of prices there. I use the more expensive ones when it's for work purposes but the ibis is perfectly decent and not all that different from a premier inn. I think I've paid around £70 for a room midweek there. Parking separate charge though.