How to set up this new form

[Maax555]

OK, so i decided to start my database again due to many errors. I have uploaded what i have so far in this new effort and would appreciate any early advice before i get into this too far. So this time I wrote down what i thought I needed in the way on tables and fields. I then created the tables and some simple forms to get me started on the simpler stuff. After creating a few forms I realised I had not entered any relationships in the database. I have tried to do this after reading up on primary and foreign keys but really not sure if I am at all getting the fundamentals correct.I hope that most of the relationships are correct. However I then added a "Similar" and "Replaces" table but unsure if I need these or how to setup, I will come back to this when i get through my initial query which is coming now after this lengthy introduction (sorry).
I have generated a form using the wizard for the table ECN-RFQ. What I want to achieve with this form is this,

1) Add a reference to ECN-RFQ Reference field. This can be anything, I will need this to be unique but as far as I can see that is not straightforward at all and I would rather tackle this later as I believe it to be more complex than I can currently comprehend
2) Add a ListBox which will list all Customers by the customer name. I can manage this but unsure if my way is the best way.
3) Add a ListBox which will list all of the purchasers from the Customer chosen in the Customer ListBox. I would like this to be dynamic as in, if i go back to the Customer ListBox and change the Customer I would like the ListBox for the purchasers to immediately update. So I am guessing a refresh macro in the after updating event?
4) Add a ListBox which will list our internal Sales people. I can manage this but again it can probably be done better?
5) Add the date received, I would like a button to pop out with the calendar which I believe I can do, however I would if possible also like the date to be populated with the current date as a default.
6) Add the date required, thankfully I can manage this.
7) Add date the job was quoted. Again I can manage this, however I think further on I will have this updated from another form or remove it from this one more likely as this form is an initial step in adding a new quote and should not really be revisited.
8) Add notes which may be relevant to the quote. Ok with this one also.

So really my sticking point is as mentioned in number 3 above. I would like to avoid any macro if possible (other than a simple refresh or similar macro).
I can get so far but the trouble is getting the criterion in the query to reflect what is in the Customer ListBox.

Also would like to have first name and surname displayed in the ListBox instead of how i have just the first name. I will play with this once posted as I believe using an alias in query is the way forward?

As always I greatly appreciate all help and advice offered.

regards Max

[Maax555]

Uploaded ECN-REF Form with SalesPerson field now showing First and Second name.