I agree with the post above, don't waste your money on a gps, simply because I doubt your instructor will let you use it at the moment anyway.
Equipment I have:
Maps - VTC, VNC, WAC, PCA. I did have an ERC-L but didn't use it so haven't bothered updating it (but am carrying around the expired one 'just in case')
Protractor - I have the square ATC one
Nav ruler - I have the ATC one - I have a 120nm one for in-cockpit stuff, and a 180nm one for planning (you only really need one though, I just decided to treat myself with the 180nm one)
Pencils and lots of em! - I recommend 2B, they're darker so easier to see the lines on the maps - you can buy a box of 20 or so at officeworks. I've carved lines into mine for scale marks for rough inflight measuring. Plus keep a couple of spares in the pocket next to you for quick access, you will drop pencils midflight
Whizz wheel (aka flight computer) - I have the '6 Jepp one, not an E6B, just a wheel
Whiteboard marker for making marks on whizz wheel - very easy to get off after and doesn't leave permanent marks on your wheel
ERSA - you can check with your FI, but I wouldn't be surprised if they make you buy one, you need to carry one in the aircraft so either you or the FI is gonna have to supply it. One suggestion though is to print out the individual pages for the fields you're going to land at from the Airservices website, so you can put it on your clipboard rather than messing around with your ERSA in flight, and the airfield diagrams are bigger so it's easier to see runway/taxiway names etc. Plus you can scrawl ATIS info and ATC info etc all over it and not need to worry about erasing it all for next time.
A4 clipboard or kneeboard - unless you're flying an aircraft with the stick between your legs where a clipboard is fairly impractical, I'd recommend a normal clipboard, I got a cheap one from officeworks - if you fold it over so the back clip part is on top, then you can store maps you're not using at the moment in flight in the middle of the fold and easily open it up to change maps
One main tip is to not buy your maps until just before you start navs. Buy them too early and they'll expire before you start and it'll be a waste of money. That being said, I have no idea how far off you are, so it may be worthless advice.
Hope all this helps :) If you have any questions about anything, just PM me, I've just been through my navs (GA, but the basic principle is the same), so it's all pretty fresh in my mind