I'm not a big fan of gadgets that only do one thing, but here are my favorite kitchen items:
Cast Iron Cookware~I collect older items, but Lodge is quite affordable. You have to treat it a bit differently from other cookware, but it's almost completely nonstick and you don't have to worry about chemical laden coatings flaking off into your food.
Carbon Steel Wok~Woks should never be nonstick!!! You use them at such a high heat that nonstick ones will burn/melt. Regular steel is the best and they are cheap too. You have to season them and make sure they stay dry to prevent rust. I love my wok!
My 6QT Kitchen Aid Mixer~I make bread every week and my stand mixer is a lifesaver! I love it! We bought a refurbished one, it was cheaper and it works great! Also great for making other things that require a lot of mixing power.
Burr Coffee Grinder/French Press~We're coffee snobs, what can I say... DH roasts our coffee in a popcorn popper too.
Regular Coffee Grinder~For flax seeds and whole spices.
Along with:
Good Wooden Spoons~Made from one piece of wood.
Silicone Spatulas~One piece of silicone (no handle to break off.)
Lockable Stainless Steel Tongs
Brass Spider~Asian type strainer
Strainers, Colanders, etc.
Glass and metal measuring cups/Measuring spoons
Kitchen Scale (A must for portioning)
Various sizes of mixing bowls
My salad spinner is from Tupperware, but when it breaks I'm buying the OXO one. You don't have to have one though. A colander and a towel will work.
A good pepper grinder is a must! Also, don't forget the importance of good kitchen knives! Buy the best you can afford. Gerber, Wustoff, Henkels, Shun, Cutco etc. are all good brands. Find ones that fit well in your hand. I would say buy a good chefs knife (or santuko), a pairing knife, and a serrated bread knife (which can cut tomatoes too.) Those will see you through most chopping, slicing, etc. Make sure to keep them sharp too.
I would suggest that you check out your neighborhood restaurant supply store. They have good quality pans, cook sheets, decent knives, etc. for really good prices.
I've also had good luck at yard sales. I found both my yogurt maker and Cuisinart food processor at yard sales (new still in the package.) Yes, a yogurt maker only does one thing, but it was $2 and I use it at least twice a week.
These are what I can absolutely do without:
Garlic press (chop it, a press damages the garlic)
Apple corer
Avocado slicer
Egg slicer
Electric can opener (a swingaway works just fine)
Microwave (yes, I'm weird)
Nonstick anything
Garlic peeler (smash with your knife)
Citrus juicer (use a fork)