Breadboarding a Raspberry Pi
I've been dabbling in electronics since the 1970s and had products used in nationwide broadcasting chains, reviewed (sometimes favourably!) in hi-fi magazines and (possibly soon) headed into orbit, and I would still consider breadboarding a Raspberry Pi a major project. 

Find a middle ground : take a look at an ARM CORTEX CPU running at 50 or 100 MHz and learn to use that. Then when that is second nature, consider taking another look at the Raspberry Pi (or whatever has replaced it in the meantime).
A good starting point is the TI Launchpads (Stellaris, now Tiva) or Hercules for 100 MHz and high-reliability hardware. Or  similar processor devkits from ST Micro or NXP. When you grow beyond the Launchpad board itself you will have experience with a more advanced CPU system than the traditional Arduinos, and it's in a package which is much easier to breadboard than the Raspberry Pi. (And at this level, "breadboard" really means layout your own PCB).

You won't even get a datasheet for the R-Pi's processor without serious negotiations (probably involving six digit numbers) with Broadcomm.

Alternatively, use the R-Pi as a component - a complete subsystem in your design that removes the need to repeat a LOT of engineering and lets you concentrate on your specific application; focus on what makes your hardware + software app unique.