For substrate you can use Daltons Aquatic Mix, about $12.00 for a 15litre bag, and put stones over this, but they will have to be fairly small, otherwise the Aquatic mix will cloud your water if it is disturbed, you can probably put some of your larger ones on top.
Be careful with the peat, as WCMMs like a ph around 7, and it may become too low if you use this. In saying that, they can be slowly acclimatised to a wide range of Ph levels, also, the peat may discolour your water.
The Aquatic mix will give you a fairly good base for the plants, I use about 20mm deep with 20 - 30mm of 5mm stones on top.
Depending on how many WCMMs you are going to put in the tank, you could probably get away with one of those double sponge filter thingies - forget the name, there are a couple of different brands out there, they sell for about $14.00 if I remember correctly.
I have a HOB on my planted community tank, doesn't seem to upset them too much! Good for water clarity, especially if you have messy fish that disturb the bottom.
As far as lights go, flourescent lamps rated at 6500 or 7000 degrees kelvin are great for plants, give enough spectrum for them to grow properly and doesn't make your tank look like a white-out like if you use the 10,000 or 15,000k lamps that you can get at the LFS.
If you are going for the cheapie power saving lamps - which is all I have over my WCMM tank in a desk lamp - Mitre 10 Mega have a range of Osram lamps which are rated 'Daylight', 23w allegedly giving out 120w of light for under $6.00. I also see they have a new range of desk lamps from Phillips, which take an 18w energy saving fluro (couldn't see what the colour temperature was, but you can always buy the correct one), which has a wee hood on it, I was tempted to buy one, as they were cheaper than the 9w clip on Jebo ones you can get at the LFS.
Coldwater plants -
Java Fern, Microsorium pteropus -down to 18 degrees
Bacopa - down to 15 deg
Hairgrass - Elocharis acicularis - down to 5 degrees
Hydrocotyle verticillata - down to 10 degrees
Some Hygrophilas down to 15 degrees
There are probably more, but I can't remember them at the moment...
Beware of the plant refered to as 'Beetroot' I think it is Hemigraphis, looks nice with metalic purple under the leaves, but will perish after a short time as it is not a true aquatic plant, same with the mondo grass.
HTH... or have I confused you more?