I'm an electronics hobbiest and am wondering if anyone knows where I can get a schematic of a circuit that will filter the battery to the ignition so that I can use one battery for receiver and ignition? I know they make these already but it can't be that hard to make one. A couple of capcitors, a diode or two, perhaps an MOV.... Anyone have a link or know where I can get information on something like this?

Moderator corrected title

Tom at Wild Hare R/C has been doing that for a long time. He's in your area there in Flower Mound. Jody at Valley View R/C has some product or another for the purpose.

I'm looking for a circuit that I can make myself. There are several products out there that do this already. Just want to play with some electronics.

Here's a device I throught would be the ticket [link=http://www.fromeco.org/products/05frcdcupm2/]D-cup[/link], I cheated and just used a 4700 uf cap from Radio Shack. There will not be many spikes with 1.66 F of capacitance in the circuit! Not what looking for but does really need to be complicated?

The battery itself acts as a big capacitor

True and a diode across the battery will help fly back spikes in the ignition box itself.

1.66F is almost enough to spot weld a battery tab, the current flow is only limited by the wire resistance.

Grab a text on RF filtering. An ARRL handbook is a good place to start. Pure capacitance isn't going to work, as w8ye said a battery is already a pretty good capacitor. Not many people are going to hand you a circuit they've spent hours perfecting in order to sell. If it was easy it would have been done years ago. You're also going to need a pretty good scope to troubleshoot with. Have fun with it.
John