This is what I am doing lately:
Directory Submissions - targeted links at high
PR directories
Blog and Forum Postings - to high
PR and frequently crawled sites
Article Marketing - submit to high
PR directories, could also serve as link baits
Link Baits - for organic linking
Three things you should always consider:
1. For SEO - Quality outweighs quantity
2. On a marketing perspective - The more backlinks, the more reach so long as you keep them targeted
3. Avoid building links with bad neighborhood sites, link farms, banned sites, etc.
