DON'T buy all the following at once, but here are all the things that I've had luck with:
A kitchen scale! (I have a little plastic one I bought at the grocery store, you don't need anything fancy, but you need it for things like "1 oz cheese"...)
Ziploc bags, little snack-sized ones. You can use these to make your own "100 calorie packs" anything you like for treats goes in there... cookies, cereals, pretzels, anything... it's wayyyy cheaper than buying pre-packaged
A pretty bowl to keep in your desk or locker at work, for heating up soups and things... those ready-to-microwave packages are more expensive... you'll also need a can opener to keep at work.
Like the PPs said, lots of fresh fruits and veggies!
Canned mushrooms (with salt)-- I don't know why, but when I am jonesing for buttery things, these trick my taste buds and are zero points
pickles (I like claussens the best) again, lots of salt (have you figured out yet I like salt???
) but very low-cal and counts as a veggie serving
canned soup-- minestrone, chicken noodle and veggie beef are favorites, these days I make up batches of homemade and freeze them.
Bouillon-- sometimes just a bit of broth can settle a craving-- other times this makes a great base for a recipe
String cheese
Dannon light n fit yogurt
Egg beaters
fat-free cream cheese and frozen bagels
100-calorie packs (yeah, I just said "make your own") but some of them are REALLY good, better than the regular versions... trial and error will tell you which ones
sugar free popsicles and fudgesicles, weightwatchers frozen desserts, etc
fat-free whipped cream in the spritzer can... have that with fresh strawberries sprinkled with a bit of cinnamon. It's yummy and elegant looking
Splenda or the generic equivalent-- good for sweet tea, lemonade, topping cereal
cold cereal- My favorites are rice krispies and golden crisp (actually I buy the generic versions of both.) The rice krispies are low-cal so you feel like you get a lot for your points-- the golden crisp makes a nice, sweet snack eaten dry
skim milk-- for cereal and tea (I don't do coffee) Will NOT work with nesquik, so don't try it, it's awful...
Swiss miss sugar free cocoa, plus calcium: nice for winter, chocolate, calcium, and only 25 calories! Reasonably good topped with fat-free whipped cream and a whisper of cinnamon-- I like this with oatmeal for breakfast in the winter
TV dinners-- lean cuisine, healthy choice, and WW brands all have lots of options that don't suck. If the servings are too small for you, add an extra side or two of vegetables. Lean cuisine makes a spinach and mushroom pizza that's pretty good. I like to top it with fresh chopped broccoli, diced tomatoes, a bit of fresh minced garlic, and some salt-- it doubles the serving size without adding any points, and all those veggies and fiber are great for you, and it tastes really good!
packaged rice krispie treats-- sweet, crunchy, just a little buttery and salty and relatively low-cal.. sometimes you can find a variety pack that has chocolatey drizzle ones.
Kudos bars or chewy granola with chocolate or peanut butter... helps satisfy that "I want candy" feeling
Viactiv multi-vitamins and calcium chews... taste like candy, but the MV is something you need daily anyway, and is zero points. The calcium is 1 point for one or 2, so I usually have 2, because they're yummy...
instant oatmeal and instant grits-- I keep these in my desk drawer for days when I want breakfast but didn't have time at home. The oatmeal is good with a bit of splenda, some fresh-ground cinnamon, and a sprinkle of.. you guessed it, SALT!
And the grits are good with just salt-- I don't even miss the butter.
And I drink lots of diet soda, because I like sweet things... and, sometimes, I use my weekly splurge on a candy bar here and there, I like "take five" the best... salty, sweet, crunchy, chocolaty, peanuty, and a little lower calorie than most other candy bars.
Sugar-free jellies and jams-- you can get the all-fruit kind, which is delicious, or the kind with splenda, which is pretty good too, but much lower calorie. I love jelly on toast, thinned down with hot water to make pancake syrup, or stirred into plain yogurt to make fruit flavors
fake butter-- nowhere near as yummy as real butter, but "I can't believe it's not butter fat-free spread" has something like 5 calories per serving, and isn't bad-- I like it on my toast sometimes, especially if there's jelly, too. It can't be used in cooking/baking, though.
Eating out:
Subway has lots of great choices, poke around in the points tool to figure out which ones you like best and what things you can add without killing your points
Chick Fil A grilled chicken sandwich meal, with a fruit cup instead of fries and diet lemonade is one of my favorites
BK and McDonalds both do grilled chicken sandwiches, but remember to ask for "no mayo", both places you can get a side of sliced apples to go along with it.
A lot of restaurants have their nutrition info online, and you can plug that into your calculator before you even leave home, to know exactly what is a good choice before you ever commit to going.
Ok, that's enough for tonight
Spend some time in the points tracker, and you're sure to find something you'll love.
Good luck!
PS- if you're not already onboard, there's a biggest loser thread starting right now for this summer, they are starting Friday, if you want to join us for moral support.
it can be done! 
