I would suggest either going with:

http://www.examplecompany.com/blog

or

Search Resource

Either of these options will add weight/pages to your examplecompany.com domain.

If you do go with http://examplecompanyblog.com, and you link to Search Resource you will gain inbound links to your main site, which also gives you increased search engine "points".

Personally, I prefer blog.companyname.com because it provides a logical separation that it is a separate site, while still giving more pages on examplecompany.com for google to index. This way, you get the best of both worlds - inbound links from blog.examplecompany.com to Search Resource and extra pages belonging to the root examplecompany.com domain.

Good luck!

<in your signature only please>