My father built brick raised beds on cement foundations. The cement had a lip a few inches out into the lawn, called a "mowing strip."

The previous owner of my house created dirt mowing strips by spraying Roundup adjacent to the flower beds and carport. It took me three years to get anything but the occasional weed to grow there (okay, my fault: I'd assumed the grass would spread naturally). If you're going to do this, you'll want to buy Roundup concentrate and mix your own; consider buying a small backpack sprayer.

Most people, I think, would just use a weed-whacker to trim adjacent to the beds.

An alternative to Roundup is cheap vinegar. Here's an interesting old thread on that subject:
http://forums2.gardenweb.com/forums/load/organic/msg0613592720186.html

You could also dig out the sod, lay down several layers of newspaper, and cover with mulch to the level of the adjacent sod. Eventually weeds would grow in the mulch. Unless you have a free source for mulch, this method would not be cost-free.

In the meantime, it doesn't hurt to try to find a free or low-cost source of old bricks or pavers. Some people will offer them for free or almost free just to get rid of them. Try Craigslist, etc. In my area there's a small "newspaper" for people selling used stuff. Check the 3x5 cards posted in the supermarket. I think I've heard that people sometimes get permission to take leftover bricks or stone from construction sites, and that the same is true for demolition sites. Ask your friends to ask their friends. Throw your shyness to the winds and ask everyone you meet: the more you get the word out, the better the chance you'll find something usable.

I'd BEG anyone for bricks - but he doesn't want them. He said he will keep trimming around the rock with the damn trimmer. He's doing it now! My NEXT place will have brick edging. Never thought of Craigslist...thanks!

Westy

Oh well, if he's doing the trimming that's another matter. I thought he was leaving it to you!

Good luck.