Sylvain,

There are quite a few options available to you. Most of the mainstream imaging OCX's support vector plugins that in turn, support Autocad DXF and DWG.

www.leadtools.com
www.accusoft.com

There are control manufacturers out there that produce just DWG controls which is a lot cheaper than the option(s) above.

www.drdwg.com

Autodesk has an OCX (DwgX) control that you could download for free? It was dependent on having a copy of Autoview for some of the DLL's it required. The benifit of this was that it fully supported all DWG revisions including the ASIC's solid-modelling.

http://www3.autodesk.com/adsk/item/0,,136987-123112,00.html

If you want even more control and essential want it for free you can use the OpenDWG foundations librarys. These are really cool and there free!

www.opendwg.com

HTH
Neil