I believe what you are referring to is program disassembly, not patching. Generally, a patch is generated using 'diff' and applied using 'patch', a process commonly known as patching
. The assumption with patch is usually that you have access to the full source code of the program, which it sounds like you do not. It does not actually help you modify the program in any way.
As for disassembly, it sounds like you don't quite have a firm grasp on the basic concepts yet. I recommend that you read this primer on x86 program disassembly
. While it won't specifically answer your question, it should at least give you a better understanding of how programs work and how to find program elements in assembly.
Finally, I believe that your specific problem may have something to do with the utility you are using. While w32dasm has been an excellent win32 disassembler for many years, it is no longer supported (since the last release in 2003) and has a few limitations. The most prominent of which are that it cannot disassemble 64-bit executables and does not work with managed languages, such as .NET and Java. Most likely the reason you can disassemble VB6 executables but not VB.NET 2010 is because after Visual Basic 6, Microsoft transitioned it to use the .NET Framework, hence the name.