DSLR Video Sliders are great, but you're limited to a short run and narrow rails. When you need something that can track for longer movements, then you're getting into track dolly territory. Track dollies are especially handy if you're working on uneven ground (cement, light gravel, short grass). Lay down a 1" PVC pipe or sturdy (yet cheap) Conduit tubing, throw your tripod on a portable folding track dolly and you can get some very effective push / pulls.
The image (above) is from the more expensive Proaim folding track dolly (seen here). For something cheaper, here are two companies (below) that take inexpensive existing folding tripod dollies and modify the casters into track wheels. Both dollies below have swiveling wheel assemblies that can be used on straight or flex (curved) tracks.
The same company making the SteadyDragon stabilizers offers a modded folding tripod dolly with three wheels on each end. The wheels are aligned to roll on the track without derailing.