As someone who just started shooting and reloading last year I can definitely relate. Man did I have questions when I started!
The essentials.
A press. I shoot IPSC and go through a lot of bullets. The only sane way to load a lot of bullets is with a 4-5 stage progressive press. In a nutshell, for each pull of the handle a progressive will do several actions like de-prime, size, drop powder, seat and crimp. Basically every pull you get a finished bullet. A single stage does one action at a time so each bullet takes several pulls. You definitely want a progressive. Dillon and Hornady are the big names. I own a Dillon 650 and I like it very much. I also purchased a case feeder which is a great option.
A scale. A scale is essential in order to weigh your powder charge. For reloading we use grains as the unit of measure. You can get digital scales for pretty cheap but I suggest paying a bit for a more accurate one.
A caliper. You need to be able to measure the Overall Bullet Length (OAL). A digital caliper can be had for not too much money.
A chronograph. A chronograph will measure your bullet velocity. This is essential for proper reloading. I shoot 9mm and mostly use 125 grain projectiles so I adjust my recipe for about 1050 ft/s (for IPSC this is ~130PF).
A case (brass) cleaner. There are different types of cleaners, I think most people use tumblers where you fill it with cleaning media (corn cob for example) and then drop you cases in and let then vibrate clean for a few hours. I had one of these but was not happy with the results (I am kind on anal and like my cases clean and shiny inside and out). I now use a wet rotary tumbler that uses tiny stainless steel pins. It cleans awesome. It is more costly to buy than the vibrating tumbler but for me it is worth it.
Reloading basically comes down to achieving the perfect recipe of projectile (bullet), powder weight and OAL to get your desired velocity. All 3 are variables and affect velocity. If your recipe is too hot, you exceed your desired velocity and it could even be dangerous and can cause injury. If you load too light you may get squibs which can also be dangerous to you or damage your gun or your gun won't cycle properly and will fail to eject. You have got to do your homework, RELOADING CAN CAUSE INJURY.
You start by referring to the powder manufacturers reloading data. They provide a minimum and maximum load range and an OAL. You will never find the exact bullet type and weight so just use the minimum weight in grains. You then setup the press for this recipe (which may take about an hour) and load about 10 rounds. Next off you go to the range setup your chronograph and shoot a few rounds and record the velocity. You will then know if you need to be hotter (more powder) or lighter (less powder). Go back home and rinse and repeat with a tweak to your recipe.
Like I mentioned earlier there are 3 main recipe variables which may or may not be clear to you.
• Powder is simple, drop more in the case and you get a bigger bang. Also very important is the particular powder burn rate. Some are slow, others fast. There are hundreds of powders out there. You generally need less weight of fast burning powder than you do of slow burning powder. Some powders are cleaner burning and less smoky. The art is to get a powder that will give you your perfect velocity with the least recoil possible and that burns clean. Unfortunately powders are quite scarce right now so you will probably end up with whatever you can get your hands on (as are projectiles and even brass).
• Overall length (OAL) affects the velocity because the deeper you seat the projectile the more pressure that will be generated and the bigger the bang. The relation is also not linear (for both OAL and powder weight) so always go slow in small increments of change.
• Projectile (bullet) affects velocity due to its profile and weight. It may be more or less aerodynamic. It may also be slipperier so to speak (eg. I load teflon coated projectiles that take about .2-3 grains less than regular bullets of similar profiles.
Finally, you need to be careful. Do your homework. Refer to the reloading data and start with the minimum load. Also ask fellow reloaders. Chances are that we may already be loading the same components you plan to and can give you the perfect recipe to start with.
Here are a few links that will help.
http://www.hodgdonreloading.com/
http://www.handloads.com/
http://www.czfirearms.us/index.php?topic=31914.0
Good luck.