Yeah, on the long side, I typically will just straight up purchase bitcoin if it is maxed out. Having funds at Mt. Gox for longs and Bitcoinica for short is how I play it.
This answer is open to anyone, my question is: when you want to place a long a MtGox do you (a) just press 'buy' at the default price in the text box, or (b) adjust the price down a little.
I've been adjusting down a little, and it takes quite some time to convert the $ to BTC. I usually choose a number half way between the default numbers that gox shows for 'buy' and 'sell'. Is this somewhat ineffective way to do it?
One thing you can try is basing your buy price on the orders that are on the books at MtGox. It may take a while for you to get your price, but this way you will have an idea if your price is doable for the amount of bitcoins you want to buy. Also try not to obsess yourself with the absolute lowest price point possible because IMHO that will lead to more mistakes and the possibly of getting a higher price point then you desired because of a missed window.
for a great display of the MtGox order book.