I may be able to help.
Can you list the current specs for your laptop? I own an Inspiron 4000, so they should be fairly similar, and I've got a spare 128 MB SDRAM module somewhere.
I also have a 6 GB hard drive.
Also, for the battery, I have some good money saving advice: Don't buy a new one, hack it!
I'm going to do this to mine, because it just died.
If you know some basic soldering skills, and have the nerve to crack open that battery casing, then follow these steps for making your battery good as new.
1) Using a set of small screwdrivers (I used jewlers' screwdrivers), crack open the battery case along the seam. Starting from the power connector helps, because it isn't as tightly sealed there.
2) Once that battery is opened up, you should see a whole bunch of red or blue cells that look like large AA batteries, which are attached to some circuitry. These are 3.7 volt Lithium Ion cells, classed as "18650" batteries. Count how many there are, and then put your dissasembled battery in a safe place.
3) Go on ebay, or your preffered online store, and type "18650 battery" into the search engine.
You should find plenty of options. Make sure that the batteries are rated at 3.7 volts and 2400 mAh, because that is the kind that Dell used in its battery packs. Buy as many cells as were in your laptop battery (usually four, six or eight) and then wait for them to arrive. I bought a set of 8 for about AU$52 (including shipping), which is a fair bit cheaper than a new battery! (I saved about $20
).
4) Draw a basic diagram of how the cells are currently arranged, and then desolder them from their links. Solder on the new cells in the same position of the old ones (there should be an indent around the + end of the cells).
5) Put the battery pack back together, although DON'T glue it together; if this doesn't work, then you should make it easy for yourself to send the batteries back. Put the battery in your laptop and charge it overnight. (It won't explode, as there is a power checking cut-off circuit in the battery).
6) Once it is charged, boot up your laptop using the battery as the power source. If this works, then your battery life should be like it was when you had bought it new! If you think all is well, then glue the battery case back together.
If these steps seem a little confusing, then there's also a video:
http://www.gearfuse.com/diy-laptop-battery-hack/
