I think you mean link exchange and it's best to do it with sites that are exactly the same as yours.
If I had a virtual assistant website, I would never ever exchange links with a web design or template site. I would ask other virtual assistants to link to me and I would link to them.
There are a few things about getting links:
1 - If you start linking to people in your blog posts etc. soon they realize and they might give you links as well. Chances are high for this to happen.
2 - You can get 1,000 free links in a few days submitting to directories
3 - Don't expect much traffic from these links.
4 - Don't expect much search engine rankings from these links.
If you want real search engine rankings and a ton of back-links, start a blog on your website and write about the things you know and you are good at.
Then place a link to your blog in your signature here and read this post:
SEO: A simple way of getting your website indexed by search engines
I know your question was about link exchange but I know your concern and this was my solution.
I hope this helps