thanks for that Ryat.  Much appreciated.  But what tech should I be researching?  I already had researched all the techs needed to increase the power of missiles and lasers, but it didn't seem to help much - well, apart from making me use up all my money lol

Thanks Zombie, I think I understand.  Will give it another go and restrict my researching to those that benefit missile damage. 

It's a great game, but requires a lot of micro-management.  (Unlike Civ3, that was my first RTS, but I had more time to determine what and where - this is quite different and I'm not used to these types of games, so I find it a bit overwhelming)

I think that as long as I restrict my research to missile damage and those ships that utilize that upgrade, I should do better.

Thanks for all your help. 

Is there a Starbase somewhere in the gravity well? If so, that could be what's chewing up your fleet - the AI will almost always upgrade only weapons and defense (strike craft as well if those are maxed and slots are left over), and such a SB is not the kind you want to go toe-to-toe with.

Generally speaking, for mid-game TEC you want your fleet supply to be 1-3 research levels higher than your capital ship crews.  The TEC faction really should be clinging to the notion of fewer higher level capital ships. 

Now, it would be nice if you told us what is killing your units.  How many frigates does the enemy have, and of what type?  What defenses is he employing?  It does sound to me like a starbase is the culprit; a small fleet like the one you describe wouldn't stand a chance against a heavily upgraded base.  If this is a Vasari enemy, you're outta luck and you'll need a much larger fleet to plough through it.  If it's a TEC or Advent starbase, just set your units to "hold ground" behavior and keep your distance; you can easily kill the starbase with bombers or Ogrovs and it's largely helpless against these attacks.

For units, you need to try and get the best balance of survivability and damage.  Upgrades are nice, but you generally want to focus on numbers first.  With only 40 LRM's, you really don't have any business with more than the first tier of upgrades, and you'd be much better served by building additional numbers.  Remember, the higher-level upgrades are balanced around huge fleets (like 1400+ command), so they're ridiculously overpriced for smaller fleets like your own.

Early to mid-game, you can get away with a nice mix of Javelis LRM (about 70%), Garda Flak (about 10%) and Hoshiko Robotics (about 20%).  Vary the proportions according to the kinds of units you encounter.  Throw in a few scout frigates into the mix to reveal mines and "look before you leap" and this simple combo can carry you into the late-game with sheer cost-effectiveness. 

Generally you either want to transition quickly (skipping damage upgrades) into the Kodiak or slowly into the bomber as time goes on.  The Javelis remains a powerful unit, but upgrading to higher-level units is a good idea as you progress.  Armour and hull is always your top research picks for TEC; they give you by far the best value of any of your upgrades.

It takes a lot of time and experience to really get into this genre.  It's got a steep learning curve, and I get that it's hard for outsiders to overcome this.  With time and patience, though, you'll learn the ropes.

Try to think of "time" as a resource in these games.  It's something you have a limited quantity of, and if you waste it you never get it back.  Using your time efficiently is a one of the best ways to improve your performance in any RTS game.  I'm not advocating being the Hare here; as much as Starcraft fanatics will say otherwise you can be very competitive at a leisurely rate.  I'm advocating being the tortoise, and keeping a constant pace at all times.  Eventually, you'll have a universal sense of pacing and timing that applies to all RTS games, and that opens new doors to enjoy this genre.