I grew it from seed years ago. You could use any lightbulb you have, I think most would work for germination. I went with a florescent light fixture because I already had it and I could fit two trays under the light easily. I used modular metal shelfs from Target.
I used old plant cell trays indoors on a table and setup the light above it on a timer. I think it was 16hrs on and 8hrs off. Anytime between 12-18hrs on should work. Just sprinkle seeds on top of soil and keep moist. I used a spray bottle of water for germination. I believe it took a month to germinate.
Also make sure after the initial soaking of soil at planting time you allow soil to dry out a bit between mistings. That will prevent mold and allow seeds to breath. You want the top layer to look lighter in color to tell you it's dried enough between watering (mistings)
Then transplant into larger container and harden outside when weather permits. I keep mine in a container and use it pretty heavily to prevent invasion of the stinging nettle. Especially by seed, you could clip seeds off and save. Also trimming the plant and combining with worm castings makes a great liquid fertilizer that adds beneficial bacteria to your soil while it boost your plants immune systems.
You could also use sunlight if available. I grew my stinging nettle in March so the above option was my best bet.
The easiest thing is either to buy a plant or forage for one, don't they grow were you live? With seeds, I don't remember what I did (weather I planted them in autumn or in spring) but I got viable seeds from Baker Creek.
I hate germinating seeds inside it rarely works out well for me. Once you have the plant it's very easy it's a weed after all.
I've heard of people sprouting the seeds for food, so if they can do that, then perhaps trying to sprout the seeds and then gently plant them, might be the way to go? I've never tried that. But I have sprouted other seeds, and have done so for germination. For food, the general rule is to soak overnight, then rinse a couple times daily to keep mold away. Another way is to put the seeds between two pieces of paper towel and keep this damp, but not a pool of water. When you see action in the seed, take a sharp knife and puncture the paper near the seed so that it doesn't struggle to get through the paper. Then cut the paper into small squares that you insert into your planting trays. I've had great success with some plants this way. I gather stinging nettle in the wild, but not seed, just young leaves. There must be some in your state, but it might not be as prevalent as it is here. Even here, you have to know where to look. Nettle prefers rich soil, and damp soil, so it seems to be riparian oriented. I find it in and around creeks. You might try to ask around via calling the university botany or ecology departments in your state and ask them where the plant might be. There might also be a wildcrafting group of some sort in your area. Try to find out and contact them.
"Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has."-Margaret Mead "The only thing worse than being blind, is having sight but no vision."-Helen Keller
It should grow well in zone 7.
I have seen nettles often along side roads and paths that go through the country and maybe even border to a leave forrest.
When you come across some, it should be pretty obvious, because it grows in huge lots together. There might be hundreds of feets, just one plant next to the other.
Diego Footer on Permaculture Based Homesteads - from the Eat Your Dirt Summit