About buying adapters on eBay...

[inkista]

Some folks find that swapping focus screens help, some folks find using AF confirmation helps (the way yours works doesn't sound quite right to me, though--it should only be lighting up when it's in focus), some folks just practice a lot until they can judge it.

You may also want to consider closing up a stop or two to get additional DoF and sharpness from your lens, and to make focus slightly less critical. I know the creamy-bokeh thing is great for portraits, but sometimes having the entire face in focus all at once works, too.

Swapping a focus screen can be fraught with anxiety, though, particularly on entry-level cameras. But Haoda and Katzeye make versions with split screens and prism collars. Their biggest drawback is that they grow darker as the max. aperture of the lens gets smaller. f/5.6 lenses tend to black out the viewfinder completely. Well, that and the price for a piece of plastic (eBay, of course, has much less expensive options).