I'd never talk anyone out of buying a new knife... 'cus that would be extremely hipocritical!

However, I have two Kabar fixed blade knifes. I have a Fullsize USMC Style and a Short "Night Fighter" . Both these knifes have been put through their paces and have held up well. They hold an edge well and sharpen easily. You can pry, hammer, chop and, of course, cut. Best of all, they are cheap!

I personally prefer the smaller Night Fighter, the bigger one is a little heavy and exsessive typically.

Now, you can't go wrong with cold steel... I only have a machette from them but it is well built and very fuctional. My buddies who have them all love 'em... inexpensive and do their job well.

For folders I have found that CRKT make some good ones. I personally have 6 of the M16 Series and have had good luck with all of them
My favorite CRKT is their Craford/Kasper I have an older generation of this knife and it has been USED HARD over the last 10 years and held up well... again this is a knife that held its edge well and sharpened easily. The frame stayed tight and I never lost a screw on this knife (the only one I have ever had). I finally broke it's tip off trying to jimmy a door open and retired it to my turnout pockets after a visit to my shop.

My all time favorite single blade folder is my Gerber Fairborn-Applegate Folder . I originally bought it becuase it was on sale 75% off and looked cool. I like how it fits in my pocket well and how easy it is to open. It has a narrow but strong blade that, again, holds an edge well (but is more difficult to sharpen).

These are just my preferances and there are many more knifes that I ahve never tried out there that may better suit your needs.