Instruction manual is here.

Exploded diagram is here.

I'm pretty sure you're saying your planer tables are not coplanar.

http://thewoodwhisperer.com/jointer-setup/ is worth watching. Despite his comments about a level, a decent level works fine for making sure your tables are flat and coplanar on smaller units like this.

On more expensive planers there are gibs that can be adjusted to fix this issue. Your part list doesn't list any gibs, so it looks like you will have to loosen the screws holding the infeed or outfeed table in place and shim it. You can use a metal feeler gauge to figure out how much need to shim it.

Also, if you're still in warranty, Delta may be able to replace your unit. If you're going down this route, I'd recommend you take a level and your unit into a service center so you can show them the problem.

Be aware that the replacement "could" be worse than the original. Be sure to check it. I recently waited 6 weeks for a replacement fence for my jointer (mine developed a twist) and the new one had a 3/8" bow in that was ridiculous.

Unfortunately the Shopmaster line wasn't Delta's greatest and there have been a lot of problems with them. It might be worth keeping an eye on craigslist in your area, as decent prices can be had on jointers fairly regularly.

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