I found some simple tools for mac that have made the pc-to-mac transition a bit easier.
Filemanagement
Although Finder is very similar to Windows Explorer, you might want something different.
Disk Order
Disk Order is an OFM (a commander-like file manager) with 2 panes and the same set of shortcuts as every other OFM you know on PC (like total commander)
You can download an evaluation copy here: http://www.likemac.ru/english/download.shtml
Basic text editing
TextMate
TextMate seems like the swizz-army text-editor for the mac. Good search options and most languages are supported and if your preferred language is not, it seems relatively easy to add it yourself.
You can download an evaluation copy here: http://macromates.com/
