Re: new to the forums, and a new rifle.
Dirt Diver, welcome to the Hide.
Nice handle, watch "The Unit" much?
As to your questions. Read the stickies in every section of this site you visit. All are full of either wise shooting & gear info, or forum policies.
And the reading thing for you will likely be your best freind, along with an occassional question by you.
Make sure that you're rig is set up solidly, & that you have one or preferably 2+ sets of GOOD quality cleaning gear & accessories. Then buy triple your body weight in ammo for your tactical stick. And easily as importantly, get a good .22LR to use as a trainer, plus lots of ammo for same. If possible set it up akin to your .300WM, if it's just a Ruger 10/22 don't overly fret. The big thing is practice, & a 22 helps one learn proper shooting technique inexpensively. And especially to develop wind reading skills.
As to equipment, you'll figure out what is on the "nice to have" list, & what's "must have" items. Both hardware wise, & information & reference wise.
The classified section's a great place to shop, as are the many vendors which support the Hide, & are listed in the classifieds section. IE who they are, & links to their sites.
You'll soon also notice that there are links posted by members, either in their siggy lines. Or just in a general posting, which lead to other great shooting sites.
Enjoy, & I hope you're used to shooting. A .300WM at times is a bit much for those new to the sport, but it can be done.