Most entry-level balls have a core in them, they're just not very strong or large. They have a pin and a CG that can be used for layout. The only entry-level reactive balls I know of that really don't have a core besides the pancake are the Tornado Warnings from Ebonite and the Groove Urethane. I'm not sure I'd call the Straight Flush from Lanemasters and "entry-level" ball, but it also has a reactive cover and a pancake core.
For plastic balls, most shops will just put the pin (and CG) in the grip center. No real static imbalance at all. Doesn't matter what your PAP, axis rotation or tilt is. The ball's not going to react anyway.
For people who are new to the fingertip grip or hooking the ball, it's a crapshoot. Unless the shop has a ball already that they can throw as a test, there's no telling where the PAP will be. Drilling it label is usually safe for most (new) bowlers, regardless of PAP. Put the pin just to the outside of the ring finger, CG towards grip center.
For higher level bowlers, they've already got a PAP, there are a few ways of finding it (put a tape at your guessed PAP, throw it, see if it moves; if it does, that's not the PAP). To lay out a new ball, decide on a layout (say, 4x5), draw a 4" circle around the pin, a 5" circle around the CG, and where they intersect will be the PAP.
There's no harm in buying a mid-priced ball as your first ball, in some sense I like that better than an entry-level ball. The only thing that will happen is that you spend about $40-50 more for it. Also, some shops have deals where you get an entry-level ball, a tote bag, and a pair of shoes for some nice discounted price. They may not have a deal like that for mid-priced balls. Just don't get too strong of a ball, Brunswick likes putting their soup monster in the mid-priced line (SwamP Monster, Goliath, Mammoth) and it's tempting to see those big hook numbers.
SH
