Your can buy the acekard 2i in some online shops. They used to be sold on sites like Amazon but not anymore. If you're in the US do a Google search for dscardworld or if you're in Europe you can search for nds-gear, you should find what you need. The Acekard 2i cards can support Nintendo 3DS, DSi and DS console.
An authorized dealer is the safest place
Neither, Go with an Acekard 2i. The Acekard 2i is the Acekard team's current top of the line card, that will work on the DSi and 3DS consoles as well (the Acekard RPG / Acekard 2's can't do this).
Check the Acekard website.
You can use the official AceKard firmware, but for more support use AKAIO (Acekard all in one)
Go to the Acekard website then click on 'Download', and you have the option of either the Official Acekard firmware, or the unofficial Acekard All-In-One firmware. (AKAIO)
40 bucks i think
The Acekard RPG is not manifactured anymore. The official Acekard Team also dropped their support for this card. You should definitly buy an Acekard 2i instead. You can buy them at any official Acekard distributor such as buy-acekard.com
You cannot play GBA games on the AceKard without the help of a Slot-2 device. Such as the Ez-Flash 3-in-1.
You can't
Now, fake acekard 2i come out, please don't choose a cheapest store to buy. You'd better buy the acekard 2i from a professional acekard 2i reseller. You can try at 4CoolDay.com, they are the Acekard Reseller for years.
Acekard 2i is better
yes, without a microsd the acekard does not work at all
24 to 30 us dollars for Genuine ones available at acekard dealers: