Or you open your DMG? Seriously, do you people ever actually use common sense with game design or does the DM just not have a purpose in your games? Actually, don't fucking answer that, this is 3.5 we're talking about.
But really. Page 184 of the DMG will give you any info you need to know about monster-design, and thus will let you know exactly how ranged attacks work out for the monster/damage it does. Just because it's not in the MM doesn't mean you're going to have cardiac arrest for having a monster draw a fucking longbow.
Here comes the lulz: random bullshit numbers based on a monster's combat role.
First of all, let me laugh at 4e for including a system where the numbers are all bullshit and
yet the RNG is still fucked. Next, let me laugh at 4e for demonstrating spectacularly the potential for fuck-ups in a system where monsters are generated via different means than characters. Then let me show you why you fail.
I can take pretty much any monster in the 4e MM to demonstrate how fucking stupid your idea is, but I'll turn to the ogres first.
Ogre savage: level 8 brute. Primary attack is +11 vs. AC; 1d10 + 5 damage. Then that ogre picks up a few decently-sized rocks and hurls them at the PCs. What's his attack bonus and damage? According to the DMG, it's going to be +11 vs. AC, 2d6+5 damage. Thus, it's to the ogre's
benefit to hurl rocks at the PCs from 40 squares or whatever the fuck distance it is.
Now, I can already see two objections forming in your head. The first one is retarded: "But what if the ogre runs out of rocks?" Fuck you for being a moron; use a bow instead of rocks, then, you goddamn retard. You're just arguing over nitpicky shit at that point.
The second is more valid: "The ogre isn't very smart. He should probably just charge up and smash the PCs."
And I'll give you that one. The ogre is a big, dumb brute, and he'll probably fight the PCs in the manner intended by the developers: no tactics, no strategy, melee attacks only, FINAL DESTINATION.
So let's move on to something a little smarter, eh?
Sorrowsworn deathlord: level 28 lurker (leader). Primary attack is +32 vs. AC, 4d10+9 necrotic and psychic damage, and the target is weakened for 1 round. The sorrowsworn deathlord's bone bow, on the other hand, is a +33 vs. AC, and it does 4d8+10 damage. The deathlord loses out on a few points of damage in exchange for the relative safety of its ranged attacks. The deathlord, not being retarded, understands this, and so it stays about 40 squares away (teleporting away as needed) from the PCs, plinking away at their HP for about 28 damage per attack. And while this will take awhile to grind the PCs down, the deathlord will prefer spending a little extra time fighting rather than spending a lot of extra time dead.
Thus, by using the 4e rules, picking up a bow becomes a clusterfuck and the PCs cry because they can't fight the sorrowsworn deathlord.