Best tips I can give as someone in the same situation:
Get yourself a Myspace, every band has one these days, maybe a proper website too.
Record a 3 track demo, it's worth saving up and getting into a fairly good studio to do this. Talk to local bands who have released stuff and ask them where they got it done and also listen to their demo's / ep's if you can so you can judge the recording quality for yourself.
When you have your demo, make up some promo packs including a short Band Biography (including your ethos etc), some decent photo's, the demo / ep, and don't forget to mention where they can catch you playing live. Don't make the promo pack too long-winded, record company guys tend to at best skim through the written stuff.
Most of the time the demo's don't even get played unless the rest of the package is of a high quality, or if there is something that catches their eye, so really go out of your way to visually impress them, as this can be the deciding factor on if they listen to your stuff or just chuck it straight in the bin without a second thought (it happens).
My last bit of advice is persistence. On the outside of your jiffy pack or envelope, put a band sticker or something else to make it stand out from the other packs that come through their door. This is because a lot of the time, they even throw stuff in the trash without even opening it (they might be having a bad day / can't be bothered). I would send all the companies a package every month if you can afford it, with your individual looking image on the outside of the pack. This way, at some point, someone is going to recognize yours over and over when it keeps coming through the door, and they will finally listen to it and that way you will get a definite yes or no response just to stop you from spamming them. even if they say no, at least you can put that particular company in the list for only sending a pack every 6 months, hehe.
That last bit of advice will be your greatest ally and weapon in the search for a contract or some interest. Nothing says "commitment" like a demo coming through their door every month, and in some cases every week.
Hope this helps. :D
