Hi Bricks2Kids (name?),
I was in your same position about 5 years ago... Like you I like Mech's, space, and had purchased and built some Star Wars sets.
A small collection, while limiting, should not limit your creativity. Figuring out how to do things with a small inventory of bricks will force you to find creative solutions to building your MOC's. I'd suggest you try and build things that you feel are mostly doable with your existing collection, and try not to build too big initially. Bigger isn't always better.
As far as growing your Lego collection, I suggest buying sets that interest you and who's themes are similar to what you want to build. Unfortunately their isn't one single best way to grow your collection with the specific parts you think you will need for the best/lowest price.
I suggest you initially focus on getting lots of standard basic bricks in the colors you like, to build up your base. The Lego Creative Boxes are good for these. If your not opposed to used bricks, garage sales, Value Village, CraigsList, etc., can be excellent places to score a good deal, but it will take time and some careful consideration...
If your looking for specific bricks, I like to go online, I personally order quite a lot of parts from BrickLink.com (I use this when I need parts for a specific project, and I always try to find a local store for pick up, or a Canadian West Coast store to minimize shipping). I also use Bricks & Pieces at Lego.Com (to get some newly released parts, usually when I want > 20 pieces of something new).
I also recommend that you get more involved with the club itself and get to know us. Often, if you need a specific part, we probably have it and may be willing to trade or sell it to you. We also have a club chat, where we alert each other of local Lego sales. Their are also potential options to get involved with some bulk parts ordering, but you will need to get more involved with the club to participate.
Here is my online Lego MOC album:
https://www.flickr.com/photos/tylersky/ ... 2775601630
If you scroll down, you'll see my MOC's, building techniques, and the size of my builds have slowly increased as I am acquiring parts and getting more skilled.
Good luck! I hope to see you at our next meeting.
-Tyler
