for non-US traders, and would like to try forex trading ASAP could try marketiva. They're adequate enough with basic analysis, signal, and alert. They've got an irc-like discussion channel and free $5 to start live trading immediately.
I've tried their platform, convenient enough to transform $5 to a fat $40
The nice thing is they accept e-gold, not much platform includes this payment method.
I really like Oanda, not just because of the good spreads but the java platform is nice and has enough indicators for me to trade simple strategies. I also love how you can use their demo for as long as you want and you can reset the balance whenver you want.
If you're looking for a broker to screw over during trades then any number of retail market makers that offer limit orders are available. IF you want to trade the proper mkt then go to an professional ecn like currenex/lava/hotspot/baxter or fx futures. Good luck getting fills on them though ... you will most likley be too slow.
Also, if your trades are med/long term that dont require any orders getting filled during periods of high volatility then any of the mainstream ecns like ib or efx are fine. If you are trying to trade aroudn news (which I again must advise against unles you know exactly what you're doing) then there really is only one platform worth using whcih is cnx. Findinf a suitable prime broker is seperate problem altogether, while most are comparable wrt liquidty and comms, you shodl really stay away from the fxcm cnx platform
Oanda has tighter spreads and computes interest on the account as well as the trades. If you have large account this could be meaningful. They do have low margin ratio margin 50:1 or less, this is limiting but some may find security in it. They do not have trailing stops and their platform is dependable, but no in bells and whistles.
I like the metatrader platform so I also have account with Interbank FX. I do not like them as well as Oanda. The marginr atio is higher, but the platform is not as stable....it cuts out sometimes, unpredictably, and the spreads are less stable, they seem to increase whenever volatility increases, even if not news time ( Oanda almost never increases speads except at news time or low volume times), this can be a problem if you have tight stops. Overall they are OK, especially for longer term trading.
Overall I like Oanda better and over time will probably migrate to them completely. IB has a very good demo account that can be used for charting using metatrader and real trading done with other broker. .