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Aphids are common but it doesn't sound like them from your description. Whiteflies are white and yellow and a search here will find you many discussions and photos of them. Spidermites are red with black spots but might be worth checking out since you mention "silk".

Hope this helps. Good luck.

Dave

Thank you for your help, but they don't look like any of those. They're not flea beetles, my bugs have very distinct wings, and they're not on that Tomato Insect Pests link, and I don't even think they're whiteflies anymore cause they're black, not white or yellow and don't look anything like any pictures of whiteflies I've found. They also don't look anything like spidermites, and they're definitely not aphids :( I don't know what they could be.

Do you notice any trails on the leaves of your plant? Could be the bug responsible for the larvae called a leaf miner?

I'll have to take a closer look, but I don't think so. They don't look like the pictures of leaf miners. The closest thing I have found is Fungus Gnats, could those be them?

Okey dokey I got some pics. The first two are of what I'm guessing are the adults, hope they are clear enough. The last one is the underside of the leaf, there are lots of black 'spots' that are too small to really see. For all I know it's larvae of some kind, or the bug's poop. And there is definitely a silk like substance on a lot of the leaves. In the first pic you can see some of it off to the right.

I got a spray insecticide. It's called Garden Safe Insecticidal Soap. I sprayed it on all the leaves and the undersides.
Thanks for all your help :) I really hope this works. Any ideas on what they are, and suggestions on getting rid of them, is very much appreciated :)

Aphids.

Squish 'em. If you use insecticidal soap, make certain the spray hits the aphid.

For real? I didn't know aphids have wings...
The spray seems to have killed most of them, I'm gonna spray every couple of days until they're all gone.

Holy aphids you're right! Just did a google, I should have trusted you! =P They are winged aphids. Damn and I just found a lady bug in the car yesterday and I let it fly away! Oh well. I'm just relieved they're not whiteflies. Aphids seem much more managable.

I too am having a problem with little black flying insects on my container tomato plants. I just noticed them for the first time today, but I have been watering at night after it has cooled and is dark. The mini-flies are only in the soil, not on any of the leaves. They are just bouncing around. Are these too black flying aphids? Could I have developed an insect from daily watering? My plants seem to need to be watered daily and both have flourished. Please help!

Ladybugs are you best friend :)

What causes these bugs to come back every year? Is there something that can be done to prevent them from returning

Those little flying bugs are "Black Fly" and suck all the juices from our tomato plants leaving the leaves crusty and dead with stunted growth. I use Sevin bug killer, and dish soap with water. They are HARD to totally remove. You can check web sites for Black Fly on tomato plants for info. Your pictures were excellent!