You just have to keep an ear to the ground. Out here, there's little interest in glow with the exception of SPAD racing and some smaller combat stuff, .25 to .32 size stuff. The SPAD racers are hot after the OS .55AX, so they aren't too interested in the larger and smaller stuff. Everyone is preferring the ease and cleanliness of electric. A lot of the old boys in the club, and a neighboring club, know of my affinity for glow planes and I am often approached by people wanting to get rid of glow equipment and planes. Most of them just want them gone, so they are happy to part with them for $50-100 and in some cases nothing more than a Coke and a smile

One guy even commented how much he liked that I like and fly glow planes. He can come to the field and get the sounds and the smells and not have to wipe the slime off his planes.
So far it's gone like this:
1. Hobbico Avistar with an OS .40 FP, free, needed Rx and battery
2. Sr. Telemaster with a Magnum .91 four stroke, $110, But did need servos, but I took them out of the free SIG Kadet below
3. a beat to death SIG Kadet with an Enya .40 and full glow accessories, and an old JR FM radio, free. This one was sadly not worth repairing, but I got some good parts out of it.
4. a SIG Faser with an OS .46FX and servos installed, only needed a receiver and battery, $75.
5. A Hangar 9, Funtana 40S with an old OS .90 rear cam, with servos, $75.
6. The Model Tech Magic with servos, only needed Rx and batteries, $60 and I got a grab bag of servos, wheel pants, and an old electrifly extreme SU-31.
I have also built a SPAD stik I built out of old election signs (not the racer with the gutter pipe fuse, but the one with the folded coroplast fuse). The SPAD stik is powered by an old MDS (mostly dead stick) .48 that a club member gave me when he could never get it to run. Come to find out, the rear crank cover seal was petrified and new o-ring had it running like a champ as long as I use 10% nitro in it (for some reason it will not run on anything higher than 10%). The coroplast is the glow equivalent of DTFB. With the exception of the 3mm stuff for some of the curved shapes it can usually be had for free if you are willing to stock up during election years.
In the queue is a 1/2A plans build that will run an .049. A SIG Kadet Mk II that my dad started building over 30 years ago when we tried RC planes the first time around (the wing is partially built, but that's all). A SIG Hog Bipe that I have a Saito FA100 for; I got the kit for $20 and the FA100 for $30 since it has bent push rods. The Hog Bipe kit is even new enough to be laser cut. I also have another used OS .91 and a Senior Telemaster short kit (purchased before I bought the completed Sr Telemaster). And a whole box of control line engines, including a sweet vintage McCoy .35 redhead and a vintage K&B Torpedo .19 with the green head.
Glow planes are just so much fun to me. The electrics are great and all, but there's just something about flying a plane with an internal combustion engine that I can't get past. Honestly, I like almost anything that flies, even multi-rotors, but planes with internal combustion engines are my favorite. At some point I want to build something big with a gas engine, but the used glow planes and engines are so affordable, it's hard to justify the expense. Plus, our club has a pretty strict noise rule and a lot of the gas guys struggle to get their big gas planes to pass sound... I have not had an issue with glow yet. I suspect the .049 might actually be too loud, but I doubt anyone will really notice since it's such a small engine and won't be perceived as loud as long as I don't run it in the pits too much. And believe it or not, I actually did convert one glow plane to electric, but don't tell anyone. It was a first gen mini telemaster that a guy had put an OS .15 on, but frankly it just wasn't right with the .15 on the nose, so I made it back into an electric plane. Plus, his conversion was not done well and it wouldn't have stayed together for too long. I have a short kit for an old Berkeley Beaver to use the .15.
I'll probably have to start stealing my teenager's ADD medicine if I want to have any chance at all at finishing all these projects. I can start a project like nothing else, but finishing can challenge me at times

In the mean time, I'll keep looking for used glow planes, and I am sure they will keep finding me. It's just like what IKEM stumbled into, he went to buy one plane and got another one thrown in! Honestly,his Super Chipmunk is way more cool than the yellow and purple plane! I'd love to have that Chipmunk, I'll bet it does some seriously mean Cuban eights! I am sure the yellow flies fine, but the Chipmunk is better!