Inserts? eBay?

Hi, I'm not even a new cloth user, as I don't yet have any nappies! I'm waiting for some to try in the post... I have ordered a couple of eBay cheapies with one microfibre insert each, but people seem to agree that MF inserts aren't great. So, my question is what sort of inserts should I use and can I get them cheaply on eBay/ the classifieds? I have some prefolds and some shaped terry nappies that I was given but never used - can I stuff my pockets with these?
My little girl is nearly 11 weeks and seems to pee quite a lot.
If my eBay nappies seem a bit leaky and rubbish, is it likely to be the insert that's the problem and should I just try some other inserts?
Thank you lovely ladies!!

We use prefolds to stuff our ebay cheapies and put the MF inserts ontop of the prefold inside the pocket. We have a heavy wetter but this combo lasts us aout 1-2 hours

I use a combo of microfibre on top as that absorbs the wee quickly and then a bamboo or hemp booster or 2 underneath as these are slimmer and more absorbant. I use Little Lamb Bamboo boosters and Easy Peasy Hemp boosters - both are about £2 each new, or you could put a wanted ad up in classifieds