Blueyonder is Cable(fibre optics) in the UK......they supply my digital TV, phone and Internet for around £65 per month.....
10Mb/386kb line is about £35 ($60 at $1.7 to £1)
Andrew...in what way is it slow....after you get past about 512Kb broadband then the differences to web browsing are virtually none unless you are downloading big pages with lots of Flash/shockwave etc
Normally you will notice a lag in ping if you are using bit-torrent or similar and uploading near capacity
Do the usual checks for spyware etc.....virus check.....make sure nothing is using your connection that shouldn't be...
Try
BHO demon to check for apparent browser helper objects such as tool bars etc that you don't want...
Try using a different web browser such as firefox or opera rather than IE (it sucks ass sometimes)
Try pinging a few of yuor favourite web sites from an MS DOS window and see if your pings are the problem...High pings = latency = slow web page responses
hope this helps