The key differences between job boards

For starters, you need to spread your web as wide as possible but still keep things targetted. So use the mainstream boards, set up daily searches on the standard boards but use the niche boards in a much more targetted fashion.

Let's list the mainstream;
Monster
Totaljobs
Reed
Planet recruit
Jobsite
Cwjobs

Some of the niche boards;
Linkedin
The ladders
Experteer
Top-consultant
Zubka

With any search you need to be as pro-active as possible, research all the above boards and decide on which is best suited to your needs. There also maybe very niche boards that are focused around specific technologies - or blogs with adsense adverts included. To take advantage of this use google as your job board and type in boolean searches. For example, a business intelligence consultant could put in;
Business intelligence and consultant and (vacancies or no agencies)
This type of search should also bring up several direct company pages.

You can also target companies directly through linkedin, get names and guess their email addresses to send your cv. This is perfectly acceptable remember they will prefer a direct approach any day of the week to paying an agency fee.

So best of luck this should be a good starting point for you and I will evaluate each board individually in our next post.