Tilt shift lenses are expensive, but if you don't mind destroying an old pair of headphones, DIY Photography shows off how to make your own with a cheap lens, headphone ear pads and a few cheap materials.
The process is actually really simple. Once you have your cheap, generic macro lens, you just need to come up with the tilt shift part. It turns out that old headphone ear pads work great for this. Combine that all together with some adhesive and you're ready to go.
Make a Macro Tilt Shift Lens from Old Headphones [DIY Photography]