A things that I noticed.

1. I am assuming that you have your images as background image because they are repeating a number of times through out the site.

2. I would advise against having frames in the site as the search engines dont view them to well and so make it hard to index them in their search engines.

3. I wouldnt have any links to on the right as everyones eye movement is left to right, so having all your links on the left would be the first thing that they see.

4. On this page http://www.hudsonltd.co.uk/CLIENTLIST.html I would put the housing association list on the left with the others because if I was just skimming through I would of probably missed them, especially as could be some high profile clients.

5. I would also change the text to not being so bold, perhaps a Verdana font at a size 11 or 12 px.

A good place to look if you are going to star learning html is www.w3schools.com got everything for beginners.

I hope you didnt think I was being to picky, Its just I am a web developer/designer so always pick on some of the smallest things that some people dont notice.