If you appreciate Shpongle, you should definitely check out other stuff by Simon Posford also, since he's produced lots of music under different aliases. He's done some faster stuff as Hallucinogen which is amazing, but if you like the laid back style more I think his best work is the album "Celtic Cross - Hicksville". More recently he's collaborated with another talented producer Benji Vaughan forming Younger Brother. You might wanna check out their album "A Flock of Bleeps". Very good ambient with some faster tracks as well.
There are a few albums out there that sound a lot of Shpongle but are by no means pure copies. Check out the artists Shulman and Entheogenic, who have both done two albums which are very nice and atmospheric.
From the non-psychedelic range of electronic music I think everybody should at least check out the following artists: Future Sound of London (especially the "Dead Cities" album), Boards of Canada (anything by them) and Autechre (check out their older stuff first). Orbital is another highly acclaimed group but the only album from them I truly enjoy is In-Sides, which is great.
So there's some stuff I think is worth checking out, hope you like at least some of them. I found these groups over a period of many years so they might be a bit too much to try to get into all at once, but take it slowly and give the music some time. Don't expect everything to sound great right away. Read some reviews to find out what's the best stuff to get started with.
