I am interested in developing a web based erp system in asp.net. Anyone knows some libraries that I can use to help in the development?

Dude , you dont need library at this level you need to learn more about MVC asp.net/MVC i think its now version 3 MVC-3 after that study ERP software application architecture design bind data bound controls to a Business Object using Object Data Source Control. also SqlDataSource & ControlGridView try this http://sourceforge.net/projects/erpnet/ i didn't download it before but i wish if this can help

Try to take a look at this eBook to see if it helps you: Develop Web ERP Software using ASP.Net 3.5, C# & SQL Server: http://www.vkinfotek.com/develop-erp-asp-software.html

the question not so clear, however, for ASP.NET MVC, you may use RAD Controls -For asp.net MVC-, it has got variety of controls that can meet almost all your requirements, i hope this can help you my friend

Hello friend, It is likely impossible to describe the whole story of developing ERP in here, but as far as I can highlight some important points, I’ll try to inculcate some important points to you, may they help you. See, first you have to specify that using which platform you want to develop the project. i.e. either using Asp .Net WebForm or Asp .Net MVC Architecture. See, if you are interested to go for Asp .Net WebForms, it'll help you develop the ERP project comparatively quickly but may be not so efficient as that could be done using Asp .Net MVC Architecture. Anyways, choice is all yours. Let me tell you some points that may help you embark on the ERP Development. First you have to gather the Software requirement specifications (SRS) and this is your job to do, you might have done it very well. All you need to do first is set up your Databases according to the SRS gathered, either using MSSQL, Oracle, or MySQL, etc. For the .Net platform to work far better, MSSQL is a better choice in my view. After you have set up your databases, you need to switch your attention to .Net Development. You have to first develop a separate class library project all by yourself, in that library, you’ll specify Data Access Components, and Business Entities, for operating the data on the .Net Platform. It might at first take you some time, if you are newbie to development, but you’ll get good at this by the passage of time. So, don’t worry. Now let’s say if you are comfortable with Webforms, you need to design an interface with the help of Asp .Net WebForms Pages, Master  page or pages, depending upon your requirements, WebForm Controls,  User Controls, Bootstrap,   and etc. Now you’ll have to see if your CRUD (Create, Read, Update and Delete ) functionality is working fine?. If yes, then just get started doing your hands dirty on development, and debug your application parallelly , if there is a need of it, using breakpoints. One more point, do use AngularJS for the single page applications, and Ajax for the asynchronous calls to server, if needed on the journey of ERP Development. Thank You.

One  thing you can do is to go through other ERP solutions (OpenSOurce) that have been built or are being bilt using asp.net and understand the whole requirements.

One such project I can refer you to is MixERP. Go have a look. Goodluck.