I noticed that the Pedersoli "Blue Ridge" flintlock guns were on sale at cabelas today so I ordered one.
Now I have a 50 cal flint lock gun on the way.

Any experienced flintlock shooters care to offer me some advise? I've been shooting cap and ball revolvers for a couple years but have never messed around with flint lock guns or rifles.

Random thoughts, in no particular order.

A white lightning vent hole liner is a good idea, it makes for noticeably faster ignition. Nearly instantaneous, actually.

I prefer english flints, they throw a great spark and last forever. I don't use leather wrap to hold my flint, I hammer a ball flat and trim to size.  Works good.

Of course you will need real black powder.  I like Goex FFFg for main charge and priming the pan. When priming the pan, I fill it up just below the touch hole.

Shooting glasses.  I shouldn't even need to say this, but I will anyway.

Never assume that just because you have not primed the pan, that the main charge cannot fire.  A good flint and a properly hardened frizzen will throw enough spark to set it off a goodly portion of the time.

You'll need some basic tools; adjustable powder measure, vent hole prick, short starter, a flask for your powder and a small flask for your primer. A possibles bag is good to have to keep all those handy on your person. If your rifle comes with a wooden ramrod, you may want to consider getting or making yourself a sturdy range rod and the appropriate jags for tasks such as cleaning, pulling a ball, swabbing the bore, etc.  

It looks like the rifle you ordered has a 1:48" twist barrel, but I don't know how deep the rifling is cut.  That particular twist rate is a compromise, sort of a jack-of-all-trades barrel.  It's meant to shoot round balls as well as conical bullets.  You will need to find a load that gives you acceptable accuracy, and there isn't much you can do to short-cut the process.  

For round ball loads, I would start by ordering some Hornady .490 round balls and pre-cut, pre-lubed patches in different thicknesses.  Common ones I've seen on shelves are .010 (too thin for my particular rifle, but I have deep cut rifling) .015 (just about right for easy loading with a short starter in my rifle) and .020 (must be started with a short starter and a mallet, but DAMN they give me good accuracy). Play with different powder charges and patch thicknesses to see what sort of accuracy you can get.  When I'm doing load work-up, I will swab my bore with a couple of patches soaked in ammonia-free windex then dry patch it between shots so that I'm operating with a clean bore.

If you can, you should try to chase down the patch that you just shot.  They generally don't make it much further than 10-15 yards from the muzzle.  You can "read" a patch.  Too thin or not enough lube, and the patch will have holes in it from the rifling or be burnt through.  A good patch will be frayed around the edges and singed in the middle, but should ALMOST look like you could re-lube it and use it again.  

If you want to shoot conical bullets, there are many to choose from.  TC Maxi-hunters or Maxi-balls may be good choices, as are Hornady Great Plains bullets.  All of these are pre-lubed.  It would probably improve accuracy to get some lubed felt wads to go between the powder charge and bullet.  

With ball or bullet, start your load development with powder charges on the low end.  I have heard that most of the rifles with your twist will throw a round ball more accurately with a smaller powder charge.  I'd start with 40 grains and work your way up in five grain increments, being careful not to exceed the manufacturer recommended powder charge.

There is a learning curve to a flintlock, to be sure, but it is very rewarding to master the art.  I was at a shooting range with some friends, and pulled out my flinter.  The other guys were shooting AR's.  I bet them a dollar that I could put a round closer to the bull than either one of them at 50 yards offhand.  Of course, my flintlock is a big barrel-heavy SOB with a long sight radius, and it just sort of hangs on the target when compared to a carbine.  I took their dollars, but the look of wonder on their faces is what I really loved to see.  Good luck!