I'll get back to you where I get the conan scanlations from when I have my external harddrive plugged in. I usually download Meitantei conan off miRC and eMule. Since conan is licensed, there are quite a number of the volumes that have bad scans. Volume 4 is one of the earlier volumes so it's a cleaner scanlation.

I asked my sister to buy me a couple of volumes while she's in Japan *squee*.