There is no straight forward answer to your question.
I was wondering how this thing happen since the first time I use this TP-Link adapter it works starightaway with Ubuntu.
To help yourself, you need to use some of the commands like 'lsusb' to display the usb devices that Ubuntu is seeing at any given point in time. The system to detect a hot plugged device is quite complicated, and there may be a problem with it.
If the TP-Link adapter worked at one point, this tells me the driver got installed, and the device got activated. Removing the hardware will not remove the driver, so it is still there. There are command to activate the adapter. Ubuntu 10.04 has an applet installed by default called Network Manager. You can access it from System-->Preferences-->Network Connections. This will bring up an application that shows the installed adapter(s), wired and wireless. There may be an icon on the top bar that looks like a 'radar' symbol. You can click it to see if your wireless adapter is connected to a network.
To tell for sure if an adapter is active, from a konsole run the command 'sudo ifconfig'. The output will show the status of the installed adapters. They may be down, in which case nothing is shown. To activate an adapter, like eth0, the command would be 'sudo ifconfig eth0 up'. For sudo, you need the root password. The wireless adapter would be named something like 'wlan0'. ( it could be different ). Activating the adapter, will not necessarily cause it to connect to a network. The gui tools are for that, or command line...
As for the different USB devices not showing up, there are many possibilities for that problem. It could be an IRQ problem or even a BIOS configuration problem. From here I can not tell.
You can find NetVista documentation online through IBM web sites. That may help you out with BIOS settings. If you can not find it, post the exact model information for the system. It will be on the serial number tag for the system. It will be 8305- something. There are many models possible.
Hope this helps.