When corporate accountants create the financial statements for a corporation there is a process they follow. This process is known as closing the books. When they close the books they create a trial balance and in the process they reconcile all the accounts including balance sheet accounts. Once the trial balance is finalized the accounts have been reconciled and the balance sheet and income statement are prepared from the trial balance. The asset, liability, and equity accounts (balance sheet accounts) are separated from the revenue and expense accounts (income statement accounts).
To get a sample of balance sheet account reconciliations will depend on the purpose for obtaining the information. If you simply want to learn how to reconcile balance sheet accounts you can go to the library and find any number of text books which will display the examples you need. Alternatively you could go to a collage book store and find a current text book with the examples you need. If you know an accountant that works in corporate finance or public accounting you could ask him/her to create an example for you.
If your purpose is related to your work and you need to get a sample of balance sheet account reconciliations for a specific company then you can start by looking at that company's balance sheet. If you are an auditor performing an independent audit the company should provide you with all the information you need. If you are an analyst you may have to dig for the information. If the company is a public company or if they issue debt (bonds) they will report to the Securities and Exchange Commission on a quarterly and annual basis (10Q and 10K reports). These reports are available to any interested party through the EDGAR data base maintained by the SEC. Corporate reports can be downloaded from EDGAR over the Internet. A wealth of information concerning a company's balance sheet can be obtained through EDGAR.
If you cannot find the information you need this way check with other analysts that report on the subject corporation. If they cannot help you try contacting the corporation itself, usually a corporation is willing to supply information to analysts and other professionals that report on their business, especially if they are trying to attract investors. It is in the corporation's best interest to cooperate with analysts and to be as transparent as possible. As you can see there are numerous sources and/or approaches that can be used to get a sample of balance sheet account reconciliations.