Lol! Well, the $65 glass holes overflow will give you the amount of flow you are looking for. It also comes with the glass drill bit for the overflow. Lowes to my knowledge doesn't sell bulkheads. If you are going to drill your own tank, you could look into the beananimal design of overflow if you really are going to DIY. Other then that, the kit from GH with teeth and the baffle is a great investment... which I wish I could have made on my tank.
The return kit from GH is pretty cool, but make sure you drill the tank really high and keep the nozzle pointed close to the surface. Either that, or drill a couple of 1/8th inch holes in the PVC to keep to keep the return nozzle from siphoning water down to your sump.
For the sump - it is actually REALLY easy - don't make it harder than it is. If you are using a 10g tank, which I think you are - Plan out the depth that you need according to what protein skimmer you are going to use. I would use at maximum 3 baffles. Go with an under over under style... where the water has to go under the first baffle, over the middle baffle and back under the last baffle. This keeps most microbubbles out of the return pump intake. Because of the size return you are using, and the type of overflow box you are getting, I highly suggest getting a Danner Mag Drive 3 pump. They are pretty quiet and very dependable. They don't add a whole lot of heat to the tank, but some may say that Eheim makes better pumps - which they do. But, a Mag Drive 3 would give you the kind of flow you are looking for - and will be dependable. When placing the glass baffles in the sump, keep them about an inch apart each. Any tighter than that and they will be hard to stuff foam blocks in and they don't keep as many microbubbles out. It's always easier to silicone in the middle baffle first, and then use some CD or DVD cases to lift up the other baffles and use masking tape to tape them in place before you silicone everything in. The first and last baffle should be about 1" to 1 1/2" from the bottom glass of the aquarium. The middle baffle is going to set the height for the rest of the sump. I'll post pics of my old 10g sump if you need me to. :D
You MAY want to consider adding a small baffle section for your overflow... the overflow will generate a lot of microbubbles, and one or two pieces of glass just for your 1" overflow pipe would work wonders towards reducing the amount of microbubbles. (basically, I keep saying microbubbles because I had a 10g sump on my old 20g tank and had a lot of microbubbles - and this is some of the stuff I would have done/changed and have changed with the new system.
Oh yeah, another thing that you will REALLY want to consider with this system is an automatic top off system. Either a float valve or a pump and controller. Keeping the water level up in the return pump chamber of the sump is a real challenge in a 10g tank/sump.
To save yourself some money on a DIY overflow, you could simply get a schedule 40 bulkhead from a reef supply and screw a 90d elbow in it and cut some slits in the elbow... and then the elbow outside of the aquarium would have to be drilled for a vent. (of course you would still have to drill the aquarium) GH sells glass hole saws for $15 each...
Still though, for the overall look and feel - I think you should go with the $65 kit from GH.
