To look at this by a process of elimination, first out would be the chop or miter saw. They are designed to crosscut long pieces of lumber, and while they can be modified to cut blanks, it's still, IMHO not a safe tool for the job. A tablesaw is better and safer, but still not ideal if you only want to cut pen blanks. You can make sleds and accessories to make it do certain jobs very well, but that's outside the scope of just making pens and cutting pen blanks. While it's the first tool I would buy for general woodworking, for pens it's further down the list. Scroll saws are also not ideal. They are specialized to cut very tight curves and do inside cutouts through drilled holes, not cut straight lines. For work the thickness of pen blanks they are slow and tend to wander.
That leaves a bandsaw. It is a compromise between cutting straight lines and curves, and between cutting large and small workpieces, but can be set up to do both jobs well (although not at the same time usually). It will work very well with 3/4 planed boards but can also cut logs, split sections and irregular chunks (with a little care and creativity). for general woodworking the most severe limitation is the depth of cut: ie, how long a piece you can cut off the end of a longer board, but this is not a major handicap with pen blank stock. Horsepower is also not a huge issue with cutting blanks. What is critical for your application is accuracy and tracking. The ability to cut straight along a drawn or measured line is very important to avoid wasting very expensive exotic materials. For good accuracy you need either a big saw with a heavy frame, or a very good quality small saw with a heavy frame. You also need the ability to mount and adjust a good quality set of blade guides. IMHO these requirements are not met in any bandsaw I have ever seen with under 10 inch wheels, and the only 10 inch saw I have seen that was good enough was the rikon square frame (or one of it's rebadged clones). I used to have one of the big box store generic 9 inch saws, and it had neither. YMMV, I have not researched bandsaws lately, and a new one that will do may have snuck in under my radar. Also the better types of blades are generally not available for these small saws. A good blade is the next most important thing. A good blade can make a marginal saw perform to acceptable levels, but a cheap blade, (or one that has been damaged or used beyond it's lifespan) can make a precision tuned saw almost useless. So, I would suggest that you search craigslist for a used saw or save up your pennies till you can afford a good new one, but don't buy a toy that you will regret, and when you do get one, don't bother using it till you get a good blade.
I concur on the book, if nothing else most public libraries have it, check it out and make some photocopies of the sections on tuning and adjustment.
Remember, buy an expensive tool, cry once, buy a cheap tool, and cry from now on.
Have fun !
