Do you mean Me
thedrone?
http://en.wikipedia.org/wiki/Methoxyphedrine
Which is of course what you've written.
Or Me
phedrone?
http://en.wikipedia.org/wiki/4-Methylmethcathinone
Which isn't what you wrote, but seems more likely.
I'm sure there's a thread on methedrone somewhere around here - did a quick search but all I could find were misspellings of mephedrone.
For mephedrone, I agree with captain codshit - lots of info in the mephedrone megathread in European & African drug discussion forum.
I use the 'wrong' end of a teaspoon, as in not the spoony end. I reckon a bump on the end of that is about 100mg.
A better way is probably to order a gram, tip it out, and divide it up. You won't get it perfect, but at least will have a rough idea of how much you're taking. I personally say 100-150mg for a first dose - others say up to 250mg. Not more than 250mg
Better yet, just buy some scales. They're not very expensive! I tend to judge it by eye, but it's much better to know exactly how much you're having.
[edit] - "they're not very expensive" was based on the "if you can afford RCs, you can afford scales" from drugs-forum.co.uk. I searched around a bit, and have seen that they do appear very expensive. I think the trick is to find one with a low maximum weight (unless you plan on weighing out 500g of drugs....). Anyway, there's a scales thread around here, so have a look at that I guess. Sorry for my premature optimism about scale pricing!