When putting a new sim card in my USB dongle/USB stick/vodem I always need the APN. Detected a new trick today: the vodafone connection manager displays the APN if you create a new profile and it can somehow retrieve the settings. Doesn't work on all networks though it seems.
I needed this today, as I was in Singapore. According to M1 advertising you could buy a mobile broadband SIM for $18, which would be unlimited internet for 3 days, anywhere. But no. I started with an M1 SIM card bought at Mustafa, and despite I had requested it for the computer, it appeared to be a voice only. The 3G light went on, but I couldn't do anything. The card didn't come with an APN in the box, just like the Cellcom one, so what I had to do was find the APN. So go to internet cafe, find APN. Got an APN (surfnet), but that didn't work. But when I created a new profile in the Vodafone mobile connection manager it popped up with choices for M1 subscription or prepaid! Very nice. So that told me it was surfnetmcard. But it didn't work. No data, despite it appeared to be connected to the 3G network.
So back to another internet cafe (just 1 SGD per hour!), and find the nearest location of an M1 shop to get the proper sim card. After 1.9km of walking I arrived at the shop and bought the proper mobile broadband SIM. However, it was extremely slow as I detected in a cafe nearby. Thanks to Google I found a suggestion to try SingTel (I was in Bugis junction as well). The top hits for "M1 mobile broadband" are already an indication to the problems M1 has. So to a SingTel shop, luckily just opposite the M1 shop. And SingTel is perfect, at least for me. Downloaded a video at 170KB/s, browsing/email all work.
Did a speed test as well. Download was 2.76MB/s, upload was 0.35MB/s so that's quite usable.