The Easy Way
There's a very easy way to use VBA script to send an email as an Outlook message. In fact, you don't even have to use VBA; you can just create a macro and use the SendObject command, but you're more likely to want to do this as part of some code.
The command you'll be needing is:
Docmd.SendObject [ObjectType], [ObjectName], [OutputFormat], [To], [Cc], [Bcc], [Subject], [MessageText], [EditMessage], [TemplateFile]
[ObjectType] - The type of database object you wish to attach to the email (table, report, etc), assuming you want to attach an object.
[ObjectName] - A string containing the name of the object you wish to send or blank if you don't wish to attach an object.
[OutputFormat] - A string containing the output format of the object. You can send an attachment in xls, txt, rtf & html formats. Leave this blank if there's no attachment. If you leave it blank having specified an attachment, you'll be prompted for the format.
[To] - A string containing the email addresses that you want in the 'To' field. They should be separated by a semi-colon, or whatever you have setup as a list separator in your Windows options. If no addresses are specified, you will be prompted for an email address.
[Cc] & [Bcc] - Same as [To], but for the corresponding fields, and not mandatory.
[Subject] - The subject of your email
[MessageText] - The message of your email
[EditMessage] - True or false, if set to true, then the email will be displayed for editing before sending.
[TemplateFile] - A path to a file containing an html template you wish to use for this email.
So, for example
Docmd.SendObject acSendQuery, "Query1", "MicrosoftExcel(*.xls)", "firstname.lastname@example.org", , , "Monthly Report", "Here are the figures you wanted", False
would send a copy of the Query1 query to your boss as an Excel spreadsheet attachment.
Depending on how you wanted to use this in your database, you might want to have a table of email addresses that can be maintained by your users, and then you could read those email addresses from the table and use them to make the appropriate [To]. [Cc] & [Bcc] strings.