For anyone who's bought the R4igold clone card from
http://www.r4igold.cn and having trouble getting it to work, this may help. I've found that the download files from their website don't have the kernel file correctly named. When you unpack the archive to a folder on your PC you may find a file called iLL.iL in it at the top level. Make two copies of this in the same folder named R4i.dat and TTMENU.DAT
Then copy the complete set of unpacked files over to your SD card, and with any luck you'll find it all works.
I've just spent the last few hours trying to get one of these cards working in my son's DSi (as the mini cd supplied was unreadable!) and only just figured out the above. You probably don't need both the file copies I've named, but I can't be bothered to check that out at this late hour.

The card is now working fine.
Also, you don't appear to need the R4iMenu folder mentioned in the instructions on the website.
Game files can just be placed in a folder on the SD card (e.g. \Games ) which you can navigate to once you boot the DSi.
If the website is down, try
http://www.linfoxdomain.com/nintendo/ds/ which has copies of all the clone firmware downloads.