I am new to SalesLogix and I want to learn how I can call my own .Net .dll from c# code in the forms designer.  

This is for SalesLogix v8 and we will be using the Web client.

Is there a beginners guide I can read?

I see where to edit the forms and scripts in "Application Architect" but I don't see where to register my .dll reference in that application.

I see another application just called "Architect" that seems to let me add a .net extension plugin but I don't know how it becomes available to the script code in the app above.

I just need a step by step guide to get me started.

I'm very pushed for time on this so I will give a free Pro license for my software AJC Sync to anyone who can help me understand the big picture, see:
www.ajcsoft.com/file-sync.htm
AJC Sync is very powerful file sync and backup software where you can create projects to sync multiple pairs of locations.  Works with all Windows filesystems, FTP, Amazon S3 and the new version just comming out supports SFTP, FTPS, MS SkyDrive and a Dropbox capabiltiy is comming soon.  You can use it to backup, keep machines in sync, publish your web site etc.

Thanks for any help.

You may be mixing up some of the Concepts here.

First of all, you state that you are going to be using the Web Client. If that is the case, you do not need to do anything with .Net Extensions.

.Net Extensions is a way to add .Net code into the Windows client.

Since you are going to be using the Web Client, there are many ways to use your .Net DLL, but it depends on what you are doing.

If you are writing Business Rules, you could do so on your DLLs, and then link the Events (or Business Rules) to methods from your DLLs.

If you are creating Controls, and using Custom Forms, then you are pretty much just writting ASP.Net code and can add the code as you would please.

If you would like to Create Custom Controls and use them within the App Architect, there are specific ways to do so.

Not sure if I could provide a Step by Step guide, as you first need to figure out which client you will customize, and what level of customizations you will require.

For all we know, you may not even need to reference or register external DLLs into the program, as in most cases you could just write the .Net code directly in the Application Architect.

This article of mine might help get you started:

Using an External Assembly for Entity Events and Business Rules in SalesLogix Web

http://customerfx.com/pages/crmdeveloper/2010/05/18/using-an-external-assembly-for-entity-events-and-business-rules-in-saleslogix-web.aspx

Thanks Raul and Ryan!  Yes I was getting confused between the Windows/Web versions and reading info on v7 confused me also.  I had never seen SalesLogix before a day ago but I have been given the task of investigating customization.

I have now been able to create my .dll and call it from the web client from an event and also a new business rule that I created that gets run when a new form button is clicked.

I have called the .dll by using a step type of "External Assembly" but is it also possible to write code in a C# code snippet that can also make a call into the .dll?  If so how would I reference the .dll in that case?

I am very greatful so you can both have a free Pro license for AJC Sync which you can download from here:
http://www.ajcsoft.com/file-sync-download.htm

That will install the trial version and then just email support and I will send you the license.  There is a beta available now (that will be released very soon) which also does FTPS, SFTP and SkyDrive so let me know if you want that.

Where you call it from depends on how to do it. If you're going to use the DLL in a C# Snippet Action then the assembly simply needs to exist in the bin (add it to the bin in the support files). Then use the fully qualified names to reference things. Code from C# Snippet Actions end up on the page itself.

If you're using the DLL from a Code Snippet Action or somewhere like that then it's a bit different. Those places get compiled so it needs the reference beforehand. To do that you need to open the code in Application Architect and then look in the properties pane for AssemblyReference and add it in there. Doing some searches in these forums will show you some examples or hints. You'll still need to add it to the bin as well so it's available when deployed.