I was under the impression that ございます was a humble form of ある. My belief was supported by websites such as this and this. However, in the comments to this question's answer, user4092 says it isn't a humble form (and also say it's used less in western Japan, which also runs contrary to my knowledge. Who is correct?
I think ございます is a 丁寧語(polite form) of ある.
～がある / ～があります -> ～がございます
～である / ～です -> ～でございます
I live in Kansai and I don't think ございます is used more frequently here than in the east (I'm not sure if it's used less, though).