Bobber stops

Looking to pick up a few "nice" bobbers. Most need stops and am curious if I can substitute a small split shot for a bobber stop. If not how do they work?

a split shot won't work too well as a bobber stop.  it will pull the bait up to the float unless the bait is much heavier than the split shot you use as a stop.  the thread stops are great because you can reel them through the guides and fish really deep sets and still be able to cast with ease.
 
If you want to use a slip float in a fixed position, use vinyl tubing to hold it in place.  It is easily adjustable too.

Tried to send you a PM but my sent box says 0. Don't know what's wrong. If you are asking how bobber stops work, I'll try to sum it up. Go to wherever you get tackle and get the little packets of bobber stops. Will be a black tubes with either green or pink string. Slide tube up line. Slide string off the line towards the rod tip and throw away plastic tube. Pull ends of string to tighten into a knot. Cut ends of string. Then slide small bead that is included with stops (you definitely need them). Then slide your slip float on. Now tie on your hook or jig. You can then add a split shot about 18" above hook for extra weight. Only needed if fishing in water deeper than 4 feet. I just started using them and I think it is the greatest thing on earth. I was always afraid to try them because I didn't understand them. You can slide that knot up as far as you need to get down to the where the fish are holding.

Has anyone seen the new thill wobble bobbers in stores yet? I've seen them advertised in magazines. But they don't seem to be on their Web site. They look real nice.

I have never had good luck with the string stops, but the small red plastic strips or bone shaped pieces that you thread your line through  work fine. Harder to find these days, but Cabela has them in 50-packs. When I was a kid we mad a loop with a piecec of rubber band and tightened it on the line, but that was 50-60 years ago, and I can't remember how we did it. 

BCAIN....... Yes, I always used the beads. They keep your bobber from riding too far up the line. It also helps with your hook set. 
 
As I mentioned, I used a stop and bead. If you don't, the float the stop can pass through the bobber and the float will ride up the line lay flat in the water, especially the tall catfish floats. You won't see the fish bite. 
 
The two stops I use can be found in Cabela's online catalog (terminal tackle).  The best one is the Dogbone (Cabela’s Dogbone Bobber Stops  -  Item K-110825) - line goes through one hole, wraps one or two turns around middle, then through the opposite hole. You can slide it up and down the line to regulate how much line you want below the float. 

 
The other (Rainbow Plastics Gizzmo Bobber Stop  - Item IK-115147)  I do the same way - wrapped around the stop - not through it. This type seems a bit more fragile. Other than that, it's the same thing.

I always had trouble with the string type stops. Afters a couple casts they would loosen and slide up/down the line. I always used mono. Maybe they have more grip on a braided line. 

I dunno if I saw it on here or read it in a mag but some folks were getting a 6 pack ring and cutting it into little strips and punching 2 holes in em with a hook point, dogbone style. So I guess you can do that in a pinch if ya don't have any stops haha. I have trouble with the string stops slippin on braid but not on mono or fluoro.

mr.crappie

When I use a sliding bobber I tie a swivel below the bobber,then tie on a short lighter # test leader so that if I get snagged,hopefuly the leader will break & the bobber will stay attached to the main line.  sam

 
Similar but different. I use braid for main line and attach my slip float to that and tie on a flouro leader with the Albright knot. I use split shot below the float to hold the float in place. My float is now between the shot(below) and the bead (above ) the float.  As Sam said if my leader breaks off I dont lose my float.
 
Ive never had a problem with the string slipping too much on my main line. Just pull it as tight as you can and it will slide when you move it. It doesnt seem to slide durring casting unless you whip the cast.  I use enough shot to make easier casts and get the distance I want.

Haha right on mikastorm.....thank you