Such data is typically only available from paid sources due to the amount of research involved in determining the identity of delisted securities, surviving entities in merger scenarios, company name changes, symbol changes, listing venue changes, research of all capital events such as splits, and to ensure that the data coverage is complete.
Many stocks that are delisted from a major exchange due to financial difficulties are still publicly tradeable companies with their continuing to trade as "OTC" shares. Some large companies even have periods where they traded for a period of their history as OTC. This happened to NYSE:NAV (Navistar) from Feb 2007 to July 2008, where they were delisted due to accounting statement inaccuracies and auditor difficulties.
In the case of Macromedia, it was listed on NASDAQ 13 Dec 1993 and had its final day of trading on 2 Dec 2005. It had one stock split (2:1) with ex-date of 16 Oct 1995 and no dividends were ever paid.
Other companies are harder to find. For example, the bankrupt General Motors (was NYSE:GM) became Motoros Liquidation Corp (OTC:MTLQQ) and traded that way for almost 21 months before finally delisting.
In mergers, there are in two (or more) entities - one surviving entity and one (or more) delisted entity. In demergers/spinoffs there are two (or more) entities - one that continues the capital structure of the original company and the other newly formed spun-off entity. Just using the names of the companies is no indication of its history.
For example, due to monopoly considerations, AT&T were forced to spinoff multiple companies in 1984 and effectively became 75% smaller. One of the companies they spunoff was Southwestern Bell Corporation, which became SBC Communications in 1995. In 2005 SBC took over its former parent company and immediately changed its name to AT&T. So now we have two AT&Ts - one that was delisted in 2005 and another that exists to this day.
Disclosure: I am a co-owner of Norgate Data (Premium Data), a data vendor in this area.