This would be better in the Defiant Heroes forum.
I am also somewhat surprised you haven't been invited by any number of SG's. Even my 48 scrapper gets blind invited to SG's just passing through Atlas and Galaxy. Hell, any zone really. There's often SG's spamming for members in the newbie areas, be patient and if you can't find teams, just start one yourself, the search tool is quite good and low level toons are most-times happy to team through the first few levels. At level 5 you'll also be sent to the Hollows. Try and avoid teams there at peak times, it's a prime teaming spot especially for newer players who don't yet realise that it's not compulsary to do the story arc there.
"Pride is all well and good but a sausage is a sausage"
For Lent I gave up...
Hope
The Hollows is a great experience for new players!! The whole zone teaches you the essential art of pathing, without which you're gonna have REAL problems moving around safely! 
Besides, Frostfire is THE most fun mission in the low levels!
As for SG's, to the OP. This would be better posted in the Defiant forum, yes. There are lots of SG's out there, some very good, some not so. I don't advise you sign up with a blind SG invite, as that will just be people looking for a prestige monkey. One SG I can REALLY recommend, is The Awfully Nice Chaps (TANC), run by a friend and one of the best and most long running SG's out there. Been active since EU launch!
@FloatingFatMan
Do not go gentle into that good night.
Rage, rage against the dying of the light.
I'm assuming you're looking for a heroic SG, and am moving this to Defiant - Heroes. If you actually want a villain SG, drop me a mail and I'll move it again.
The Echelon would most likely have you ...
Send a tell to @Callista or @mackero next time you are on and we'll try and organise you into one of out SG's 
Feel free to send @Toxus a tell too, we're always looking for more active members, and welcome new players and old hats alike.
For the record, we are known as Justice Squad, and our SG colours red and white. We wanted something just slightly corney
Ask me about joining Honourable United. Go on ask me!
Ooooh! Pray, do tell me about Honourable United
Please
Please 
"Pride is all well and good but a sausage is a sausage"
For Lent I gave up...
Hope
I recently migrated from World of Warcraft, and Guild Wars, to CoH/V. One problem I have, is that alot of the low level areas are empty, so I cant get teams easily, which means I have to solo, which takes forever and a day.
Im what some would call a veteran, with over 500-600 World of Warcraft hours, and a good 300+ Guild Wars hours. I have reached the level cap of these games on numerous occasions.
If any active SGs on Defiant want me to join, it my be my honour, as most of the time, im all alone
PM me for more details
Thanks
Ukiy