1. Your corp channel can be your friend. There is a Help channel (to which, I believe, n00bs are automatically subscribed for a while), but in my humble, it gets clogged with idiots and scammers (the latter because they know there are innocent n00bs there to rip off).Your corp channel (to which you also get automatic subscription) is a tolerable substitute. People there range from n00bs like you to seasoned vets listening in for the h*ll of it. Some will drop tips, many will tell tales of Mistakes they have Made (which you can thereby avoid replicating), and some will even drop the odd ISK to those in need.
There is also the possibility of finding comrades in nearby systems, and linking up to share missions. Two can mine faster than one; two can kill more rats than one. Yes, you share the rewards, but then again, if you (and your friend) can do two missions (safely) in the time that you alone would do one (with risk), isn't it worth it ?
2. You can pick your missions. Agents belong to "divisons" -- Security, Marketing, Legal, and so forth. And somewheres there are multiple versions of a chart that tells you what sorts of missions each division's agents offers -- so many percent kill; so many courier. [edited:: Look at http://eve-survival.org/wikka.php?wakka=AgentDivisions ]
Armed with that information, you can (to an extent) pick who you go to. Suppose you've just bought a cruiser, and are thinking of level 2 missions. But you're not certain if it's set up in the most efficient manner. You could always try it out ratting (but the rats sometimes stay away). Or, you can find a level 1 agent, who offers kill missions 90% of the time, and do a whole set of try-outs, against live enemies, but of the sort that a frigate or destroyer ought to be able to do. It won't be a perfect test, but it's better than diving straight in and getting Blown Away.
Or, if you need to run missions, but maybe need to be afk for periods (not a good idea, but sometimes necessary, especially after a night of curry), you could select agents that give courier missions. You'll earn less per mission, but (in general) they will be shorter than combat missions, and (if you stay out of lo-sec) you probably won't get shot at. Or you could get your mining ship, and go and work for a mining agent. You'll need something with teeth, because s/he will throw in combat missions, and because most mining involves rats as well. But you will have long(-ish) periods, wehn all you need to do is fill your hold and then either shuttle to station and back, or drop it into a jetcan.
3. Read the mission spec. The agents (breaking the fourth wall here) aren't real people: they're computer programs. They don't know what ships you have or what skills. So, now and again, they will ask you to do things you just can't achieve. Like going Ice Mining, when you don't have the skills, the ship, or the mining laser thingies. Or they will offer a courier mission that will take more space than you have. Sometimes those can be done by splitting the cargo and running the route two or three times, but sometimes it is one or two large units, which you can't fit in. And sometimes the pick-up location for a courier run will be hi-sec, and the destination will be, but the route will require ducking in and out of lo-sec.
In these cases, remember that you are allowed to refuse missions. You can refuse one mission from an agent and not (despite what the on-screen warning says) suffer a loss in standings. If you do, simply leave that agent alone for over 4 hours, and the standings-loss risk will reset. Go and fly for another agent (or drop back into Real Life for a while).
4. Lo-sec is not certain death. It just seems like that, when you lose a ship there.
Some missions (and some markets) require you to go one system into 0.4 space. There is the risk that the gate is guarded; equally there's the possibility it's not. If you use a throwaway ship (a Reaper, say), then all you risk is the fittings (and, obviously, any mission goods). You check the hi-sec side, and Local channel, to make sure that there's no obvious peril, then jump through. And wait. Your UI will show if there are ships waiting: if there are, you're still cloaked. You can either AFB back towards the gate and hope to make it, or warp out (probably to a station, using "Dock" so that there are only seconds before you'll be safe inside). If yuo're on a mission, you wanted a station anyway, to collect or deliver stuff. Your Local will tell you how many people there are in-system, and what chatter there is. When you need to go back, undock, and immediately warp to the gate you want warping to zero.
This means, when you arrive, you will immediately be within jump range, and can go through even if you're being fired on. Do not fire back -- a) it excites the yarr-gang, and b) the gate crews don't like letting agressors through. Just jump in (possibly with shield reppers running), jump through, and jump away (just in case they've put a second crew on the hi-sec side, to try and scare you back through -- remember, they can't attack you in hi-sec without Concord getting p*ssed).
I need a nap now.
Read, enjoy, comment maybe.