The best way to find a good provider in your area is to read online reviews from a reputable source or a well-known online forum. It is usually a good idea to find multiple reviews on providers before taking them into account, because everyone's opinion is different, therefore one review can not be used as an indicator of the quality of a broadband service provider.
Also, although online reviews can be a good source of information, don't forget traditional offline research methods, for example asking friends and family members who have internet service from the same provider.
This would be especially useful if the people you ask live within the same area as yourself, because it seems that in most cases, the reliability of ISPs varies greatly from area to area.
There are two types of broadband connection currently available, these are ADSL and cable. ADSL is the inferior of the two, due to the fact that it relies on circuitry that was originally designed for telephone calls and therefore has limited bandwidth capabilities.
Cable broadband, on the other hand, relies on wiring that was built with the future in mind. meaning that incredibly fast speeds are available to any users who use this method of connectivity to access the Internet.
The only downside to cable broadband is that it is usually quite expensive, meaning that most users tend to opt for the cheaper ADSL connections, because although they are known to be slower and more unreliable, they are usually sufficient for users who simply wish to browse the Internet and play the occasional online game.
For business users, however, ADSL is generally a bad idea because for most organisations, reliability of internet connections is critical, especially for those business who use VOIP technology to make and receive telephone calls over the net rather than using traditional phone lines.
Finally, one thing that is important to remember is that ADSL reliability is usually similar amongst all of the service providers, especially in the UK where all ADSL connections actually run over the same network, but are re-branded as being provided by several different companies.