Can we buy this or have to go DIY?
If you can get a 2 socket incandacent 10 gallon canopy from a used pet shop that fits over your tank gallon, you can just replace the stock incandacent bulbs with the 2 10 corallife colarmax compact fluorescent or you 2 10 watt 6500 K daylight compact fluorescent(GE brand are cheap at Wal-Mart and work great for a low tech). I purchase a used 2 bulb incandacent 10 gallon canopy and that is what I did. Heck! if you were my neighbour, I would have happily given you an extra two bulb 10 gallon canopy for free. The other thing that you can do is purchase two clip on desk lamps, put the compact fluorescent bulbs(10 watts in each) and aim them over the tank. The problem with this is that you would have to leave the tank unconvered and this may cause issues if you decide to put in fishes that are jumpers.
As far as otos and neon tetras go, these fish are compatible and will go exist in a 10 gallon. The problem is that they are also the most sensitive fish of all. The neon tetras are prone to neon tetra disease and if you don't quarantine fish and get one that has this condition, it could spread to other fish in your tank and wipe out the whole population of fish. This happened to one member who was forced to tear his tank down. You may be better off to get cardinal tetras if you are looking for fish as pretty as neon tetras.
The rule is, no more than 2 otos per 10 gallon tank. When choosing otos be sure to buy ones that have been in the seller's tanks the longest, have big bellies. Also, be sure that you acclimitize them properly. I am only mentioning this as otos are another fish that seem to have a high natural mortality rate but if you do what I say may increase their chances of survival. I also find that the ones I feed microwaved zucchini seem to survive the longest.
For a 10 gallon, I would err on the side of understocking, rather than overstocking, so personally I would not put in anything more than one Betta fish, or make it a shrimp and otocat tank only, with otocats and cherry and or amano shrimp. The Amano shrimp, IME are excellent consumers of algae and dead plant matter and so will help to keep any algae under control. They also tend to be pretty hardy. I have one in a tank that has tripled in size and even survived ammonia spikes. It was still alive when everything else in the tank was dieing. Shrimp also place minimal bioload on a tank.