To blank it out you need one of the shapers mentioned earlier, I would suggest a saw, but I had a go with the hatchet for my firewood log attempt, this left the final piece more rustic, as there were deeper gouges from the hatchet.
As you can see from the pictures, I made a cuboid, but you could make it any shape you like.
Once you have the basic shape done, you can work on it with progressively finer tools- like a plane, then sander, then finer sandpaper..
- You should have a go at using a plane if you haven't already- they are really fun, and they make a big mess of wood curls everywhere.
A belt sander is really helpful, but not necessary. I put mine upside down in the vise so I could bring the work to the tool, not the other way round, which is easier for smaller stuff.